การสำรวจความลับของเมืองอเล็กซานเดรียโบราณ
ตั้งแต่อเล็กซานเดอร์มหาราชถือกำเนิดขึ้นจนถึงยุคปัจจุบัน เมืองนี้ยังคงเป็นประภาคารแห่งความรู้ ความหลากหลาย และความงดงาม ความดึงดูดใจที่ไม่มีวันสิ้นสุดของเมืองนี้มาจาก...
From icy mountain summits to bustling riversides, the line between two countries often tells a story more vivid than any map. International borders can follow ridgelines and rivers or cut arbitrarily through plains and towns. For example, the Iguazú River plunges over 80 meters into the Paraná Basin, forming Iguazu Falls that straddle the Argentina–Brazil frontier. In contrast, the boundary between Portugal and Spain—the ancient La Raya—has remained virtually unchanged since the 13th century, making it one of Europe’s oldest continuous frontiers. This article tours the planet’s most remarkable borderlines, from the highest peaks to the quirkiest enclaves, weaving historical context with travel insights. Along the way, the reader encounters peaks, waterfalls, fences, and unique border crossings, each illuminated by facts and anecdotes.
Borders can be natural wonders or bureaucratic oddities. Some follow rivers or mountain crests, while others trace straight lines on a map. The notion of an “interesting” border is necessarily broad: it might mean dramatic scenery (like a waterfall shared by two nations), human ingenuity (an opera house split between two countries), or geopolitical significance (a tense demilitarized zone). To prepare, one might review quick facts: the world’s longest boundary is shared by the USA and Canada (8,891 km), whereas the shortest land border is only 85 meters at Spain’s Peñón de Vélez de la Gomera. Some boundaries – like the Denmark–Sweden bridge or the Bosporus dividing Europe and Asia – we will also touch on, though the focus is on the most unusual and storied crossings.
By examining these borders in detail, we can appreciate how geography and history intertwine. Each section below follows a theme – whether “natural wonder” or “divided community” – to guide readers from broad context to fascinating specifics. The goal is to understand not only where the lines lie, but why they matter: culturally, environmentally, and for travelers.
Towering at 8,848 meters, Mount Everest marks not just the planet’s apex but also the highest international boundary. “Mount Everest is not just the tallest peak on the planet,” notes a Himalayan researcher, “but with Nepal to the south and China (Tibet) to the north,” the summit itself sits on the Nepal–China frontier. Climbers on the south face in Nepal or the north face in Tibet (China) literally stand in different countries at the top. Thus the world’s loftiest mountain is simultaneously the world’s loftiest border.
Everest’s two sides also reflect different access. Nepal’s classic South Col route (via Khumbu Valley) has been open to foreign climbers with permits since the 1950s. Climbers pay steep fees – on the order of tens of thousands of dollars – to secure Nepali permission and to hire guides and Sherpas. By contrast, the Chinese (Tibetan) side was closed after China annexed Tibet until permits were allowed for expeditions. Travelers hoping to trek or climb from Tibet must acquire special Chinese and Tibet permits. For example, visiting Everest Base Camp on the Tibetan side requires both a Chinese visa and two Chinese-issued permits (a Tibet Travel Permit and an Alien’s Travel Permit). Even helicopter tours at 8,000+ meters must follow these regulations. In practice, most foreign expeditions approach Everest via Nepal. From the summit, climbers can theoretically step into Nepal on one foot and China on the other, an experience unique to this peak.
Everest also has cultural border lore. Nepalis call the peak Sagarmāthā (“Mother of the Sky”) and Tibetans Qomolangma (“Goddess Mother of the World”). Indeed, both countries have claimed symbolic ownership. In 1960 Chinese Premier Zhou Enlai controversially asserted that the entire mountain belonged to China, prompting Nepalese leaders to respond that the summit “has always been within our territory”. Ultimately, after tense talks Mao Zedong suggested placing a boundary marker atop Everest. In 1961 Nepal and China signed a border treaty, confirming that the crest runs through the summit.
In short, Everest blends extreme geography with human story. Permit rules, historical debates, and even climbing records all revolve around this ultimate border. Visiting requires months of planning – seeking mountaineering permits, preparing for altitude, and coordinating with Nepali or Chinese agencies – but even trekkers to nearby base camps witness how this mountain literally unites two nations.
The roaring curtains of Iguazu Falls straddle the frontier of Brazil and Argentina in South America. Here the Iguazú River becomes the international border: after winding through uplands, it drops some 80 meters in a 2.7-kilometer-wide horseshoe of cascades, marking the boundary between Brazil’s Foz do Iguaçu and Argentina’s Puerto Iguazú. UNESCO declared the combined national parks on both sides as a World Heritage Site in 1984, highlighting the falls’ grandeur.
This waterfall system is among the world’s largest: about 275 individual cataracts lie along a basalt escarpment. Tourists can experience it from both countries. Argentina’s side offers extensive boardwalks and (if one is brave) catwalks literally above the thundering torrents, including a vantage point directly over Garganta del Diablo (“Devil’s Throat”), the tallest single drop. Brazil’s side, meanwhile, provides panoramic views of the entire falls. The two sides have complementary facilities – boat rides get people close to the falls (often spraying them) on either side – but one cannot walk across without immigration clearance.
Interestingly, just downstream lies a tri-border area where a third country, Paraguay, abuts Brazil and Argentina near the confluence of the Parana River. But at Iguazu itself it’s only two nations meeting in nature’s theater. Rainbows arch through the mist, and lush subtropical jungle surrounds both parks. Historically, these falls were “discovered” by Europeans in the 16th century; today they draw over a million visitors per year. One can explore viewing platforms, ride a Zodiac boat into the falls, or simply hike trails, but all the while the national boundary flows through the middle of the spectacle.
At the other end of Asia’s largest countries, Vietnam and China also share a spectacular cascade. Ban Gioc – Detian Waterfall lies on the Quây Sơn River at the Guangxi–Cao Bằng border. A pair of parallel falls plunge 30 meters down wide basalt steps – in total 300 meters across, making Ban Gioc Vietnam’s widest waterfall. Half of the falls straddle Vietnam, half China, embodying the frontier between them.
Like Iguazu, Ban Gioc lies in a lush gorge and attracts local tourists. Bamboo rafts ferry visitors close to the falls, often amid clouds of spray and rainbows. Fun fact: Chinese tourists on the upstream side often wave at Vietnamese on the river below (and vice versa) as the boats pass. Historically this region saw conflict (border disputes in the 1970s) but now enjoys cooperation. Beyond sightseeing, visitors can explore nearby caves, temples, and a former military fort. Approaching the falls itself is less regulated than in past decades; it was once necessary to register with border authorities, but today the only real requirement is standard visa rules and entry to Vietnam (from Hanoi or Ha Long City, one can drive up to Cao Bằng province).
In the remote Guiana Highlands of South America, Mount Roraima stands guard at the meeting point of Venezuela, Brazil, and Guyana. This ancient flat-topped mountain (“tepui”) occupies a unique tripoint boundary: about 5% of Roraima lies in Brazil, 10% in Guyana, and a full 85% in Venezuela. The sandstone cliffs rise abruptly over 400 meters above jungle, forming an almost horizontal summit plateau. It is famously said to have inspired Sir Arthur Conan Doyle’s novel The Lost World.
On the summit of Roraima itself stands a solitary cairn marking the international borders. Atlas Obscura describes it as “a whitewashed stone pyramidal marker … where the borders of Venezuela, Brazil, and Guyana all meet”. Hikers who complete the multi-day trek to Roraima’s top (normally from the Venezuelan side) can actually stand with feet in three countries at once. The cliffs host unique plant and animal life, much of it endemic, making the trip both a geopolitical and ecological journey. In practical terms, Roraima is accessible through Venezuelan territory (tours depart from the town of Santa Elena de Uairén, often involving a two-day jungle hike). Brazil and Guyana have no direct overland routes to the summit except via Venezuela. For those who do make it up, the panorama spans three nations – a fitting epitaph for a mountain whose very geology makes borders visible.
While not an “uneven” land border, the Strait of Gibraltar forms a maritime boundary between Europe and Africa and thus between Spain (and the British overseas territory of Gibraltar) and Morocco. At only about 14 kilometers wide at its narrowest point, it is arguably the closest international crossing between two continents. This slender channel has been a crucial waterway for millennia. The great Pillars of Hercules of antiquity were identified as the Rock of Gibraltar and Jebel Musa on the Moroccan side.
Even today, ferries ply the strait daily, and some intrepid swimmers attempt the crossing (though the currents are dangerous). The rock itself is a familiar symbol, topped by a Union Jack and loomed over by Barbary macaques. In recent years there have even been revival proposals for a fixed link: a 2021 report noted that the UK and Morocco discussed building a tunnel or bridge between Gibraltar and Tangiers, potentially linking into high-speed rail networks. Any such project would be a modern engineering marvel. For now, visitors can stand on either shore and see the other side of the world. Given its length of only a dozen kilometers of water, some consider this gap effectively “zero” distance – yet crossing it formally still requires passports.
Spain’s little-held outpost of Peñón de Vélez de la Gomera in North Africa boasts the planet’s shortest land boundary. This tiny rocky peninsula, once an island, was attached to the Moroccan coast by an earthquake in 1934, creating an isthmus only about 85 meters long. That is now the entire frontier between Spain and Morocco here. Consequently, Peñón de Vélez has the world’s smallest terrestrial international border. The Spanish flag flies atop the peak, where a small detachment of troops and a few official buildings stand. Due to its military status, tourists cannot simply stroll across. Nonetheless, Peñón de Vélez is a remarkable geographic oddity: a Spain-Morocco border so short that a leisurely stroll from one end to the other would take seconds.
By contrast, the boundary between the United States and Canada is often celebrated as the world’s longest international border, spanning some 8,891 kilometers. Its route crosses forests, plains, and lakes, from the Atlantic coast through the Great Lakes and Great Plains to the Pacific. Its sheer length also makes it symbolically “undefended” – there are no permanent military forces stationed along most of it, unlike many other borders. In fact, it is colloquially called “the world’s longest undefended border”. Of course, that does not mean it is open. Thousands of official ports of entry have immigration and customs officers on duty (especially since 2001), and many segments are fenced or monitored. After 9/11, both countries tightened security with more patrols and surveillance.
The human and economic integration along this border is intense. It separates densely populated areas (New England, the Great Lakes, the Pacific Northwest) and also wild lands. Akwesasne, a Mohawk Nation reservation, straddles the line at the junction of New York State and Quebec. In Akwesasne and some communities around, homes and even commercial buildings are bisected by the boundary, leaving residents with one door in the U.S. and another in Canada. As one report notes, “several buildings (including a bowling alley) lie in two countries at once”. Each side’s laws apply to their portion; for example, a bar in such a building might have to clear its customers inside before a provincial or state curfew. Yet the everyday impact is minimized by freedom of movement under NAFTA (and now USMCA) provisions and by local arrangements. A traveler can cross many points simply by showing a passport or NEXUS card. In rural areas, even dog-walking lines on maps can be crossed in winter by snowmobiles without routine patrols.
Stretching over 5,300 km along the crest of the Andes, the Chile–Argentina border is one of the longest on Earth. It runs from the dry Atacama in the north, over 50 mountain passes, down through the Lake District and Patagonia, to Tierra del Fuego. The difficulties of this frontier echo its geography. In many places, the border cuts through glaciated mountains and volcanoes. Among the most famous border monuments here is the Cristo Redentor de los Andes – a 1904 statue of Christ installed on a high mountain pass (Uspallata at 3,832 m) to celebrate a peaceful resolution of Chile–Argentina territorial disputes. This symbol of unity looks out over both countries, reminding passersby of the friending of two mountain nations.
Travel between Chile and Argentina is largely by a handful of Andean tunnels and roads. Key crossings include the Paso Los Libertadores (north of Santiago-Mendoza) and the Cardenal Samore Pass (near Bariloche). Extreme points include the Alberto de Agostini National Park in Tierra del Fuego, where even the small Diomedes Island is split between the two countries. Historically, the border shifted after wars of independence (and the War of the Pacific indirectly). Today travelers with passports and vehicles can drive from one side to the other at official checkpoints. The scenery of the two countries changes abruptly at the line: snow-draped peaks, glacial lakes, and high plains characterize the Andes, while once over the pass one enters a different climate and often a different language (Spanish, as a practical matter, in both countries).
In the tiny Dutch–Belgian town of Baarle, the international line is a bewildering patchwork of enclaves and counter-enclaves. Here one can find 22 Belgian enclaves inside the Netherlands and 7 Dutch exclaves within those enclaves. A visitor standing in the town center might cross in and out of Belgium and the Netherlands multiple times on a single stroll, often without realizing it. The boundaries cut through streets, farms, and even buildings. Some restaurants and shops in Baarle have dining rooms that fall on both sides; indeed, one café famously had to move customers from the Belgian to the Dutch side at 10 pm each night to comply with the stricter Dutch closing law.
This labyrinthine border dates to medieval feudal land divisions and treaties. Today, the two countries coordinate municipal services so seamlessly that residents rarely face immigration checks as they go about daily life (both Belgium and the Netherlands are in Schengen). Still, differences remain. Each country’s flag flies only on its enclaves, and in some cases Dutch and Belgian parking, postal, and tax rules can differ. Maps of Baarle must be drawn in color; a border enthusiast can walk a special “enclave tour” to see how the border zigzags around houses and fields. For travelers, Baarle is a tourist oddity: one can literally cross an international frontier by stepping over a painted line on the sidewalk.
Perhaps no building is more emblematic of a friendly border than the Haskell Free Library and Opera House in Derby Line (Vermont, USA) and Stanstead (Québec, Canada). Completed in 1904 by a wealthy donor who wished to serve both communities, the library/opera house was deliberately built right on the boundary. The division is physical: one half of the reading room lies in Canada, while the main entrance and office are in the U.S.. A visitor may browse books in one country, then step a few paces to check out a volume in the other – technically crossing a border indoors. For about a century the border was essentially open here; readers would leave from the U.S. entrance and stroll straight into Canada inside the library.
Post-9/11 security tightened things. Canadians can still approach the library via a narrow public sidewalk on Canadian soil, and an official sign even notes: “Canadian residents may visit the library on foot without clearing U.S. Customs”. However, as of 2023 the policy changed so that only patrons registered with the library may use the Canadian entrance – their library card effectively serves as permission to cross. In practice, most visitors now enter and exit through U.S. immigration at the front door and then enjoy the Canadian side within.
This curious landmark still functions as a library and performance venue. Its stage is split by the border line (an orchestral concert can start in one country and end in another!), and it even has dual postal addresses. Tourists visiting Derby Line often make a point to cross the doorframe, symbolically standing in two countries. The Haskell exemplifies a “divided community” turned advantage: the neighbors cooperated to provide a shared cultural space, letting the border be a novelty rather than a barrier. It remains a charming case study in how ordinary life can glide across an international line.
Entry to the Haskell building is governed by national laws. Americans arriving on foot from Vermont show their U.S. ID at the U.S. door; Canadians may use the back sidewalk entrance and simply show a library card to U.S. customs officials. (Children and many students have family member cards.) Technically, one must hold a valid ID for the country of entry. In recent years library cards (free for residents) became a requirement for the Canadian approach. Otherwise, visitors often enter via the U.S. side, scanning passports. Thus, crossing the international line at the Haskell is formal but expedited for those using the intended routes.
No border inspires more caution than the 240-kilometer Demilitarized Zone (DMZ) between North Korea and South Korea. Created by the 1953 armistice that halted the Korean War, the DMZ is a 4-kilometer-wide buffer running roughly across the peninsula. Although “demilitarized” in name, it is arguably the world’s most heavily fortified border. Each side has laid minefields and planted sensors along its side, and tens of thousands of troops patrol the line. Sporadic skirmishes, defector escapes, and even attempted assassinations have occurred across this boundary. North Korea’s side (the Military Demarcation Line) is famously guarded by plaques, bunkers, and guard posts; South Korea has leveled forests to maintain sight lines.
Visitors from the South can enter the DMZ only on guided tours (usually to Panmunjom at the Joint Security Area or to observation points). They see vestiges of the Cold War: empty villages like Kijŏng-dong across the border with propaganda speakers, massive flagpoles (“flagpole war” tall standards), and rusting tanks that once lined the trenches. A concrete pillbox marked “Fence No. 27” or similar is left where the armies once exchanged fire. Security is tight: anyone found crossing outside official points could be shot, and photography is restricted.
It bears noting that despite the peace talks here and there, the Korean border remains unresolved in treaty. Today, formally neither side even recognizes the other’s regime, adding to the border’s tension. Nevertheless, a kind of stalemate persists. In 2018, a limited joint effort began to remove some landmines from the Joint Security Area, raising hopes of slowly lessening the danger. For now, however, the Korean DMZ stands as a stark example of how an international boundary can also be a flashpoint – a reminder of conflict even amid beautiful mountains and forests.
In the heart of Europe, the Poland–Ukraine border forms the EU’s eastern edge. Stretching roughly 535 kilometers through rolling countryside, it also doubles as one of the longest Cold War-era borders still in effect (it once separated the Soviet Union from NATO). Historically it has shifted after wars, but today it is fixed as Ukraine’s frontier with two EU states (Poland and, to the south-east, Slovakia).
Until 2022 it was relatively quiet, with open markets and legal crossings. A giant land-art installation symbolizes the solidarity here: each spring, Polish farmers have sown sunflower seeds in the shape of a giant fish that spans the border, so from an airplane you literally see a “river” of yellow crossing into Ukraine. That artwork signifies friendship: migratory carp were released to swim through the cornfields. This border area is known for shared cultures (the Polish city of Przemyśl has a Ukrainian minority) and for cross-border festivals.
However, since the 2022 Russian invasion of Ukraine, this frontier has become a safety valve for millions. By early March 2022 over 2.3 million Ukrainians fled their country, and the majority – about 1.42 million – entered Poland. Border checkpoints like Medyka–Shehyni and Korczowa–Krakovets have seen record lines of cars and foot travelers. Poland has had to scale up relief efforts to accommodate the influx (housing, medical care, etc.). Smuggling and human flow have also surged, as people and goods move West. The frontier now has temporary transit restrictions in places and has even seen the Polish border guards don stiff uniforms.
Despite wartime tensions on Ukraine’s eastern front, the Poland–Ukraine line has mostly held fast. It separates not armies but mainly refugees, volunteers, and aid convoys. One unusual landmark on this border: a 1982 anti-nuclear protest-themed mural by artist Jarosław Koziara which, when sown with green rye and yellow wildflowers, resembles a giant carp crossing the border. It serves as a reminder that nature and art can cross divides, even as history makes them visible from space.
In the Himalayas between India and China lie only a few official crossings, each at very high altitude. As of the mid-2010s, three passes were open for limited use. Nathu La Pass in Sikkim (4,310 m) was reopened in 2006 after 44 years of closure, becoming one of three land trade posts between the two countries. The others were Shipkila Pass in Himachal Pradesh and Lipulekh Pass in Uttarakhand. These ancient routes were once part of the Himalayan Silk Roads for wool and salt.
Today Nathu La has a gated market on the Indian side and a barred gate on the Chinese side. Traders and pilgrims (not casual tourists) use it to exchange goods: India sends wool and rice to Tibet, while China provides raw wool and medicines. Access is by permit only (Indians must register with the army; foreigners need an inner-line permit for Nathu La). During the brief warmer months, one can hire an official guide to cross and see the Chinese guard post. Similarly, Lipulekh now connects India to Tibet, and Shipkila to an alternate Trans-Himalayan route.
These Himalayan borders also reflect historic tensions. In 1962 India and China fought a brief war that closed many frontier routes. Ever since, these passes reopen slowly as confidence-building steps. For the adventurous traveler, organized treks to Kailash pilgrimage sites sometimes use Nathu La, but casual independent crossings remain complicated by bureaucracy. In sum, the India–China frontiers are trails and high roads that once linked civilizations, now carefully managed by permits and patrols, and set against spectacular yet forbidding mountains.
On the Caribbean island of Hispaniola, the forested mountains of the Dominican Republic abruptly give way to denuded land in Haiti. This stark contrast forms a visible line even from satellites. An environmental researcher notes, “The Haiti–Dominican Republic border is visible even from space – such is the extent of deforestation on the Haitian side”. On the Haitian side (the west of the island), wood charcoal remains a primary cooking fuel for many; trees have been cut for firewood and farming. On the Dominican side (the east), deforestation was banned decades ago and energy was shifted to gas and electricity. As a result, forests cling on the DR side while Haiti’s hills are brown or blackened.
The border here is more than a political line; it is an ecological boundary. Conservationists worry about the loss of watershed and biodiversity in Haiti, where only about one-third of the original forest cover remains. The Dominicans have launched reforestation efforts and protected national parks that span the frontier (like the chain of mountain parks along the ridge). Some NGOs run tree-planting on both sides of the border. But poverty in Haiti continues to drive wood harvesting for charcoal. Tourists driving the border road will notice the sudden color change – a warning that this border must be managed not only by guards but by ecology.
More than three decades after German reunification, one can still see the Cold War divide of Berlin in the city’s nightscape. At night from space, East Berlin’s skyline glows orange under its old sodium-vapor lamps, while West Berlin shines a cooler white under fluorescent and LED lights. The reason is practical rather than symbolic: when the Wall stood, East Berlin lit its streets with old-style orange sodium lamps (standard in the Soviet Bloc), whereas West Berlin adopted more modern, energy-efficient white lights. According to The Guardian, East Berlin retained about 30,000 of these gas lamps until recent years, long after the city’s reunification.
Thus the border is still seen not by militaries but by electrical engineers. An image taken by ESA astronaut André Kuipers from the International Space Station highlights this divide: the Brandenburg Gate lit in warm yellow contrasts with the West’s sodium-white glow. Germany is slowly replacing all old lamps for efficiency, and experts say the light-divide will fade within a decade. For now, however, tourists on a clear night – or even visitors walking the former “death strip” – can notice subtle differences in streetlight color. Berlin’s enduring light pattern is a metaphor: physical walls are gone, but the vestiges of division linger in infrastructure and memory.
In southern Africa, a single point has famously been claimed by four countries: Zambia, Zimbabwe, Botswana, and Namibia. This so-called quadripoint lies near the town of Kazungula on the Zambezi River. On one bank sit Zambia (north) and Botswana (south), while Zimbabwe (south) and Namibia (Caprivi Strip, north) come very close to meeting at a single spot. For years it was debated whether all four borders actually touched at one concrete point or if Zambia and Botswana had a tiny gap between them. In 2007 the governments agreed that a short 150-meter stretch of riverbank connected Zambia and Botswana, allowing a direct border there.
Until recently, crossing this point was a dinghy ferry that ran hourly, famously one of the busiest busier border crossings on the continent. In 2021 a new four-lane Kazungula Bridge opened, linking Zambia and Botswana directly. This engineering feat crosses the disputed point without touching Zimbabwe or Namibia, affirming the separate border segments. Zimbabwe already has a bridge to Zambia at Victoria Falls (30 km east), and Namibia has one upstream at Katima Mulilo (across the Zambezi to Zambia). But Kazungula is unique: it is the juncture of four sovereign lands (albeit two of them only separated by river). In practice, a traveler can drive from Zambia to Botswana via the bridge in minutes, and see Namibian waters on one side and Zimbabwe on the other. It remains a popular point for photo-ops – you can stand at the Zambia toll plaza and wave at the Botswana customs booth, pondering that just meters away is a link to two more countries.
On the outskirts of Bratislava, Slovakia, sits a whimsical monument to open borders. At a forest park called Szoborpark stands a triangular picnic table whose three benches each lie in a different country: one in Slovakia, one in Austria, one in Hungary. This tripoint (and small sculpture garden) was created to symbolize unity and cooperation between these neighbors. Tourists can stroll out and sit down with friends so that, physically, each person remains in his or her own nation while sharing a single meal.
The picnic table is just one of several markers here (others include triangular stone monuments). The site is about 20 minutes from Bratislava and easy to reach by road. It has become a lighthearted attraction – families pose leaning across the table holding one corner, exclaiming they’re “eating lunch in three countries at once”. Nearby trails offer hikes that cross the invisible lines. This spot reminds us that many borders – especially within the EU – are much more symbolic than restrictive. In this peaceful corner of Europe, the line on the map is brushed over by casual day-trippers and picnickers, just as intended by the park’s artists.
The border between Norway and Sweden stretches over 1,600 kilometers through the vast forests and mountains of Scandinavia. Unlike much of history’s borders, this one is known for amity rather than conflict. Norway and Sweden peacefully split after the dissolution of their union in 1905, and since then both sides have treated the border as open countryside. There are no checkpoints for residents moving between the countries; most crossings are simply signposts on forest roads.
One can even ski or snowmobile across the Norway–Sweden line in winter with no customs to clear (local rules require only staying on the trail!). The famous Three-Country Cairn lies a bit further north, where Sweden, Norway, and Finland meet on a little river island. There, an old stone pyramid (erected in 1897) marks the tripoint, and hikers often build small cairns on it as a tradition. In summer, travelers in this region follow trails with stone cairn markers (sometimes iron tripods) that plainly show national boundaries.
Overall, life in the Norway–Sweden borderlands is high-caliber friendship. The two countries are both in the Schengen Area, allowing free passage. Villagers near the border routinely cross for work, shopping, and family visits. Environmental cooperation is high: wildlife (like moose and bears) roam freely across the line, and park management is often joint for transboundary parks. For adventurers, the Swedish mountains actually have border-bridges that say “Welcome to Norway/Sweden,” and friendly signs with maps in multiple languages. In short, here the border exists mostly on maps and for administrative purposes (taxes differ, for example), rather than in any palpable tension.
The frontier between Spain and Portugal, sometimes called La Raya, is remarkably one of the oldest in Europe. It was set by treaties in the 12th–13th centuries and was firmly fixed by 1297, and has remained virtually the same ever since. (Portugal’s boundaries have remained “almost unchanged” since the mid-1200s, after it completed the Reconquista of Algarve.) This makes the Iberian border one of the longest-lasting political lines on Earth. It currently runs some 1,214 km from the Minho River in the north to the Guadiana River in the south. Today both countries are in the Schengen Area, so for most travelers the line is a formality. Yet La Raya retains cultural significance: border communities share dialects and festivals, and no Schengen checks dampen tourism.
Interestingly, this frontier also hosts a novelty: a cross-border zip line. At Sanlúcar de Guadiana (Spain) near the Guadiana River, adventure-seekers can hurtle 720 meters over the water to Alcoutim (Portugal) at about 80 km/h. At the end of the ride, riders are one hour behind (due to time zones) and can ferry back. It’s widely promoted as the only zipline in the world that crosses an international border. So one can say “I flew from Spain into Portugal” quite literally.
Yes. The Limite Zero Company operates a cross-border zipline here, touted as the world’s first. Riders start in Spain’s Sanlúcar de Guadiana and land across the Guadiana River in Alcoutim, Portugal, on an opposite hilltop. It is indeed the only zipline that begins in one country and ends in another. Participants simply ride like tourists (passport in hand, as Portugal is abroad) and then return by ferry. The thrill is not only the speed but the novelty of crossing an international line mid-air. According to travel reports, the setup takes care of border formalities, so riders can enjoy the thrill legally and safely.
Beyond the Spain–Portugal example, ziplines across borders are exceedingly rare. Still, the idea has captured imaginations. Enthusiasts note that you can cross the Rio Grande by zip in Mexico–US parks, and rumor even suggests a proposed zipline from Austria to Slovakia (never built). None compare to the Iberian one in fame, but it highlights a theme: creative border crossings. As a result, “zipline” has become a buzzword among border tourists.
Practically speaking, border ziplines pose safety and legal questions (what happens if someone loses a shoe mid-flight?). In all known cases, operators manage identity and travel docs beforehand, and the line is short (720m in Portugal). We list this under “unique” rather than “common” because it’s a novelty attraction, not a serious transit option. In future, who knows? Drone delivery or ultra-long skate could cross borders, but for humans, ziplines are the current pinnacle of fanciful crossings.
Waterways often define borders – think the Danube, Rio Grande, or Mekong – and sometimes require ferries or boats to cross. In some remote areas, rivers form the only link. We already discussed the Kazungula pontoon ferry on the Zambezi, which connected four countries’ road networks. Similar examples worldwide include ferries linking South Korea and Japan’s islands, or the seasonal boat between Morocco’s Ceuta and Spain (Europe–Africa crossing by sea), or the wildlife pontoon linking Brazil and Guyana at Oiapoque-Vila Brazil.
A few river borders have creative arrangements. On the Oder–Neisse border (Poland–Germany), rapids and ferries exist where no bridge stands. The India–Bangladesh border has dinghy crossings and footpaths along the Naf River. Even in developed areas, one might cross country lines by road tunnel under a river (e.g. Channel Tunnel between UK and France, though not over water).
Legalities can be interesting: often international law says border runs mid-channel or along one bank. For instance, on the Paraguay–Brazil–Argentina triple frontier, river islands shift with floods, changing who claims them. In the Americas, one can cross from Argentina to Brazil by boat at the Iguazu or Parana rivers. European inland ferry services (e.g., on the Rhine between Switzerland and Germany) require little more than a passport stamp. The key point: when a border lies on water, countries typically agree to ferries, bridges, or floating checkpoints rather than impassable walls. Seasonally, some rivers freeze, temporarily becoming drivable paths (northern Alaska/Canada, or between Sweden–Finland in winter).
Finally, many nations are separated by mountain ranges with high passes as the only links. Besides Everest and the Himalayas (see Nathu La, Lipulekh, Khunjerab), other famous passes include Khyber Pass (Pakistan–Afghanistan), Khyber (UK-controlled for a time), and high Alpine passes like Mont Blanc (France–Italy) or Brenner (Austria–Italy). The Andes have many too: besides the Cristo Redentor statue, roads like the Caracoles and Jama pass traverse Chile–Argentina high in the Andes.
For travelers, crossing a mountain border means altitude and weather considerations. Some passes open only in summer (like Karakoram or Himalayas) and require permits. In the Alps, freedom of movement in Europe means one can hike or ski from one country to another without formalities at shared trails. High passes often have dramatic terrain: glaciers, storms, and abrupt climate shifts. But they also offer unique views, like seeing a different homeland valley below. As with ziplines, high mountain borders hint at adventure. The need for maps, guides, and awareness is imperative, as some passes have patrols or minefields (e.g. Turkey–Armenia’s remote mountains). In all cases, crossing by foot, pack animal, or offroad vehicle is a reminder of earlier trade and pilgrimage routes that once linked cultures across impossibly high divides.
Visiting novel borders requires the usual travel documents – passports, visas, and sometimes extra permits. However, some unique borders have special rules:
– Dual-use buildings (Haskell Library, Baarle houses): Entry often uses local ID or a membership. For instance, Canadians only need a library card to enter the Haskell from Canada.
– High-altitude passes (Nathu La, Everest Base Camp): Aside from passports, one needs country visas and local permits. Nepal requires mountaineering or trekking permits for Everest, while Tibet requires a special “Tibet Permit” and an “Alien’s Permit”. Nathu La (India–China) requires an Indian Inner Line Pass or border permit, and Chinese entry papers. Typically, these must be arranged through approved travel agents or authorities in advance.
– Protected parks and villages: Enclaves or special zones (e.g. India’s Lipulekh Pass, Druze border areas) sometimes need military or police permission. Tourists must register, hire guides, or join official tours.
– Schengen vs non-Schengen: For EU internal borders, no formal visa is needed. But crossing from a Schengen country to a non-Schengen neighbor (e.g. Norway/Sweden before 2001, or now for Brexit and Eastern Europe) will need proper passport control.
To prepare, travelers should research bilateral agreements. Useful steps include: obtaining a passport valid for at least six months, checking if a visa-on-arrival is available, and looking up specific crossing rules (especially if entering via unusual points). When in doubt, contact local embassies or tourist boards. For river or ferry crossings, check ferry schedules. For symbolic crossings (like the Tri-Table), no formalities apply beyond public access. Always carry ID even if no checkpoint is expected.
Seasons can make or break a border adventure. Here are some guidelines:
Planning tip: Always look up local cross-border conditions. If traveling to multiple borders in one trip, stagger the schedule – for instance, climb high mountains in summer and visit lowland falls in autumn when crowds are smaller. Keep an eye on local news for weather warnings or diplomatic tensions. Seasonality, more than anything, determines the accessibility of many remote or extreme borders.
While many borders are harmless tourist sites, some carry real risks. Here are key considerations:
In summary, border tourism requires sensible precautions: plan the paperwork, use official routes, and stay informed of local conditions. Ironically, many of the most interesting borders are the safest – they are stable places visited by travelers. But the truly volatile ones (W. Sahara, Kuril Islands, etc.) often have no tourist facilities anyway.
Borders evolve with politics. Current hotspots hint at possible new lines or reunifications. For instance, there are active negotiations and proposals from Morocco and Spain to formalize their maritime boundary in the Western Sahara. In Asia, India and China still discuss their Himalayan frontier (though near Nathu La it is settled, long disputed elsewhere). Africa has minor unsettled segments in the Sahara. Climate change poses a future challenge: melting polar ice may open passages (Northwest Passage) turning once-remote waters into new borders.
Technology is also changing borders. Passport controls are increasingly replaced by biometric gates in Europe, and projects like the EU’s Entry/Exit system. On an extreme level, proposals surface for wild ideas: as noted, tunnel or bridge projects like the Gibraltar link, or large-scale border tourism infrastructure (visionaries once even proposed an Arctic Corridor to link continents). Meanwhile, movements like Catalan or Scottish independence (if realized) would redraw internal lines.
Nevertheless, most current borders are likely to persist. Few sovereign boundaries are under serious change today. Many bilateral border treaties were only recently settled (1980s onward). The end of the Cold War and the breakup of the USSR and Yugoslavia saw many border redrawings, but that era has largely passed. Looking ahead, integration trends (like visa-free travel) may make borders more symbolic. Yet as geopolitics show, the idea of dividing lines remains powerful, so one should watch diplomacy and treaty updates – albeit with the understanding that dramatic changes are the exception, not the rule.
History has seen borders come and go. In recent decades, new countries have appeared: South Sudan’s 2011 independence created fresh boundaries with Sudan and Uganda. Conversely, other borders have melted: within the European Union, many internal frontiers (like East–West German or Austria–Hungary) have become meaningless. The Schengen Area in Europe effectively erased passport controls across dozens of borders, even if the lines remain on maps.
Looking to the future, some theorists predict even more fluid borders with globalization. Some suggest national lines might blur as trade zones or city-states grow. However, counter-trends exist: sharper controls on migration, satellite surveillance, and nationalism can reinforce borders. In border tourism, we already see a mix: historic dividing walls (the Great Wall of China, Hadrian’s Wall) now draw visitors without fighting; new barriers (like fences along parts of the India–Pakistan line) deter visitors.
Ultimately, borders are as permanent as politics and geography allow. Areas with unsettled populations or ethnic groups may see future referendums or arbitration (e.g., the Kuril Islands dispute between Russia and Japan). But most of the world’s major land boundaries have been stable for decades. In sum, any disappearance or creation of borders will likely come through diplomacy or plebiscites rather than sudden shifts. Travelers should therefore expect to see the same frontiers for the foreseeable future – even as our ease of crossing them may change with technology and policy.
What is the shortest land border in the world?
The record belongs to Spain’s Peñón de Vélez de la Gomera (offshore near Morocco). This tiny Spanish-held rock is connected to the Moroccan mainland by an isthmus only about 85 meters long. In 1934 an earthquake turned a sea channel into dry land, creating this minuscule stretch. No border on Earth is shorter.
Which countries share the longest border?
The United States and Canada share the longest international boundary, about 8,891 kilometers. It runs from the Atlantic to the Pacific through forests and waters. For many years it was considered “undefended” since neither country has troops posted along it. By contrast, the second-longest border is Russia–Kazakhstan at ~7,600 km.
Is there really a place where four countries meet?
In southern Africa, the town of Kazungula in Zambia is famous for this. The Zambezi River borders four countries: Zambia, Zimbabwe, Botswana, and Namibia. In practice, Namibia and Zimbabwe do not actually touch; two narrow bridges link the four lands. Nonetheless, at Kazungula the boundaries converge closely. A new bridge directly connects Zambia and Botswana at this point. In a symbolic sense, four nations meet here, even if one pair is separated by just river channels.
Can you stand in three countries at once?
Yes. Tripoint markers exist where three borders meet. One example is Mount Roraima in South America, where the peaks of Venezuela, Brazil, and Guyana converge. Another is the Slovakia–Austria–Hungary junction with its famed triangular picnic table in Szoborpark. In Europe, a stone cairn at the northern Three-Country Point lets one stand in Norway, Sweden, and Finland simultaneously. These places let thrill-seekers claim a foot in each of three lands just by standing on the marker.
Which border is the most difficult to cross?
The term “difficult” can mean different things. Militarily, the Korean DMZ is the hardest and most dangerous – only special tours allow crossing. Physically, some mountain or jungle borders are extremely challenging: for example, the treacherous Darien Gap on the Panama–Colombia frontier has no road and is often impassable on foot. Politically, places like the India–Pakistan line in Kashmir are highly restricted. In practical tourist terms, the toughest borders are those closed to civilians (North Korea’s border), or those that require extensive formalities (e.g. crossing into Tibet from Nepal).
Borders are lines on maps, but they come alive through culture, nature, and human endeavor. From Mount Everest’s summit to a tiny Spanish rock in Morocco, each border has a story. Some are drawn by glaciers and rivers; others by treaties and treaties’ echoes. We have seen how geography (waterfalls, mountains, lights) and history (wars, art, politics) combine to make certain borders uniquely compelling.
Travelers often find that even a fence or checkpoint can prompt deeper questions: Why does this wall stand here? Who travels back and forth, and how do daily lives straddle it? Many of today’s interest lies in the combination of freedom and restriction – the chance to cross an international boundary while still feeling a world apart on either side. The borders described above serve as living classrooms. They remind us that human societies draw lines, yet also build bridges: of commerce, of understanding, and of friendship.
Ultimately, exploring borders can be as much about looking inward as outward. It prompts reflection on national identity, environment, and our place on Earth. As border tourism grows, one can hope for continued cooperation among nations, so that curious visitors can safely enjoy these edges of civilization. Whether gazing at a waterfall straddling two countries, walking a library hall on two continents, or sharing a picnic table with people in three nations, we find that borders, for all their gravity, often invite connection. In that spirit, may this guide serve as a useful companion for the armchair explorer or the adventurous traveler, inspiring journeys not just across frontiers, but into the stories that have shaped them.
ตั้งแต่อเล็กซานเดอร์มหาราชถือกำเนิดขึ้นจนถึงยุคปัจจุบัน เมืองนี้ยังคงเป็นประภาคารแห่งความรู้ ความหลากหลาย และความงดงาม ความดึงดูดใจที่ไม่มีวันสิ้นสุดของเมืองนี้มาจาก...
ฝรั่งเศสเป็นที่รู้จักในด้านมรดกทางวัฒนธรรมอันล้ำค่า อาหารรสเลิศ และทิวทัศน์อันสวยงาม ทำให้เป็นประเทศที่มีผู้เยี่ยมชมมากที่สุดในโลก จากการได้เห็นสถานที่เก่าแก่…
แม้ว่าเมืองที่สวยงามหลายแห่งในยุโรปยังคงถูกบดบังด้วยเมืองที่มีชื่อเสียงมากกว่า แต่เมืองเหล่านี้ก็เป็นแหล่งรวมของมนต์เสน่ห์อันน่าหลงใหล จากเสน่ห์ทางศิลปะ…
ในโลกที่เต็มไปด้วยจุดหมายปลายทางยอดนิยมสำหรับนักท่องเที่ยว สถานที่ท่องเที่ยวอันน่าทึ่งบางแห่งยังคงเป็นความลับและผู้คนส่วนใหญ่ไม่สามารถเข้าถึงได้ สำหรับผู้ที่กล้าเสี่ยงพอที่จะ...
กำแพงหินขนาดใหญ่ซึ่งสร้างขึ้นอย่างแม่นยำเพื่อเป็นแนวป้องกันสุดท้ายสำหรับเมืองประวัติศาสตร์และผู้คนในเมืองเหล่านี้ เป็นเหมือนป้อมปราการอันเงียบงันจากยุคที่ผ่านมา…
