The Tower of the Winds in Athens – known in Greek as the Horologion tou Kyrristou (“Clock of Cyrrhus”) or simply Aerides (“Winds”) – is an ancient octagonal clocktower that once served as a public timepiece and weather station. Built of gleaming white Pentelic marble by the astronomer Andronicus of Cyrrhus around 50 BCE, it stands about 12 m (40 ft) tall with each side 3.2 m across. It is located at the north end of the Roman Agora (marketplace) in Athens, between the Plaka and Monastiraki districts, on a gentle slope of the Acropolis hill.
For millennia it has fascinated scholars and travelers alike as one of the world’s earliest scientific monuments – a “meteorological station” adorned with mythology, science, and ancient engineering. The tower’s importance lies in its innovation (sundials, a hydraulic clock, and weather vane), its architecture (the first documented Corinthian columns on a public building), and its cultural symbolism (reliefs of the Anemoi, the Greek wind gods, carved on each facade).
The Tower is traditionally dated to the late Hellenistic period. Ancient sources and modern archaeologists attribute its construction to Andronicus of Cyrrhus (Kyrrhestes), a Macedonian astronomer, around the reign of Julius Caesar (1st century BCE). It was known as the Horologion of Andronikos (Greek Horologion tou Andrónikou), meaning “timepiece of Andronikos,” and also simply Aerides (“Winds”). Roman authors mention the building: the architect Vitruvius (c. 25 BCE) describes it in his De Architectura, calling it the “Tower of the Winds,” and notes the engineering of its sundials and clepsydra. The Roman writer Varro (1st century BCE) also refers to this monument in his agricultural treatise, indicating it was already famed by ~37 BCE. Its Greek name Horologion means simply “timepiece” (ἡρολόγιον in classical Greek).
Modern scholars debate its exact date of completion; while 50 BCE is widely cited, a few sources have suggested a somewhat earlier date (late 2nd century BCE). Regardless of the precise year, it was finished by the mid-1st century BCE. Its construction required enormous resources – the same rare Pentelic marble used in the Parthenon – suggesting either a wealthy patron or state support. (Some historians speculate Julius Caesar or Augustus may have subsidized the Roman Agora’s construction, into which the Tower was integrated.)
The Tower’s history spans several eras: from Roman Athens to the modern era. Important milestones include:
Date/Period | Event |
c. 50 BCE | Construction completed: Andronicus of Cyrrhus builds the octagonal Tower in the Roman Agora. It immediately serves as a public clock and weather vane for merchants. (It likely replaced or complemented earlier small sundials in the ancient Agora.) |
37 BCE | Roman author Varro mentions the tower in De Re Rustica, confirming its existence. Vitruvius (c. 20–10 BCE) also describes it in detail. |
1st–2nd c. CE | Roman period: The Tower continues in use. A small square water cistern (“Clepsydra of Athens” on the Acropolis) feeds its hydraulic clock. Sometime in these centuries, Emperor Hadrian expanded the Roman Agora (but the Tower predates Hadrian). It’s possible the clockwork and wind vane fall into disrepair by the late Imperial era. |
4th–5th c. CE | Byzantine (Christian) era: The Tower is converted into part of a Christian church, likely a baptistery. Excavators found traces of a chapel inside and a cemetery outside. Contemporary sources (e.g. the pilgrim records) confirm a church-like use. It was even called the Temple of Aeolus in the 15th century, reflecting folk association of the wind gods with a pagan sanctuary. |
1456 CE | Ottoman conquest: After the fall of Constantinople, Athens becomes part of the Ottoman Empire. The Tower is used by Sufi Whirling Dervishes as a tekke (dervish lodge), with a carved mihrab added on the southern wall and Islamic inscriptions painted inside. This sacred status famously protected it from removal; Lord Elgin planned to take the entire Tower to Britain in 1799, but the Dervishes’ guardians prevented it. |
1837–1845 | Excavation: After Greek independence, the fully buried Tower (then half-buried under earth and debris) is excavated and cleared by the Greek Archaeological Society. This unveils much of its structure, and a copper engraving by Andrea Gasparini (1843) preserves its mid-19th-century appearance. The surrounding Plaka neighborhood even took the name Aerides. |
1916–1976 | Restorations: Minor restorations occur during 1916–19 (led by scholar A. Orlandos) and in 1976. In the late 20th century, much of the roof was reconstructed, and metal reinforcements added to preserve integrity. |
2014–2016 | Major Conservation: A thorough conservation campaign (2014–2016) cleaned the marble, stabilized the structure, and conserved the paintings. The tower reopened to the public in August 2016 after ~200 years. Multispectral imaging revealed the original polychrome decorations – a deep Egyptian-blue ceiling and red-and-blue meander border – once bright against the marble. Today it is a museum/site within the Roman Agora complex. |
The Tower is an octagon – eight equal faces each facing a cardinal or intercardinal direction. Architecturally, it blends styles: the two small porch-entrances (one northeast, one northwest) once had Corinthian columns of Pentelic marble (fragments survive today) while the interior doorways used simpler Doric pilasters. In fact, the conservation report notes the interior capitals are Doric and the exterior Corinthian – a rare mix, suggesting an experimental architectural approach.
Feature | Description |
Plan | Octagon (8 sides), each facing one of the 8 winds (N, NE, E, … NW). |
Height | ~12.1 m (39.7 ft) from base to roof peak. |
Diameter | ~7.9 m (26 ft) overall footprint. |
Material | Pentelic marble (white, crystalline). |
Base | Three marble steps forming a low platform. |
Columns | Two small Corinthian columned entrances (NW, NE). |
Frieze Reliefs | 8 marble panels (metopes) with the eight wind gods (see below). |
Sundials | Carved vertical lines on each face (sundial hour marks). |
Water Clock (Clepsydra) | Internal hydraulic clock (see below) fed by spring water from Acropolis. |
Roof | Original conical marble-tile roof (restored in 2016). |
Weather Vane | Bronze Triton on roof, rotating to show wind direction. |
One unusual feature is the blended architectural orders: the austere Doric style inside (plain square columns) versus the ornate exterior Corinthian touches. The tower’s intact sculptures and finial base also show it was once colorfully painted: traces of red and blue on the Ionic capitals were found during cleaning. The engineering is precise – for example, the roof’s marble slabs interlocked without mortar, a sophisticated Hellenistic technique.
Most striking are the eight wind deities carved in high relief on the frieze above the tower’s doors and windows. Each panel corresponds to the wind that blew from that direction. In Greek mythology these winds were personified gods called the Anemoi. Their names (north to north-west) are Boreas, Kaikias (Caecias), Apeliotes, Eurus, Notos, Lips (sometimes called Livas), Zephyrus, and Skiron. (Some ancients listed 12 winds, but Eratosthenes’ 8-wind scheme was used here.) Each god is shown fully mobile with attributes hinting at their powers:
These iconographic details match descriptions in ancient poetry and the tower’s inscriptions. (Later Greek writers like Aristotle and Timosthenes formalized the eight-wind system; the Tower’s choice of these eight reflects that classical scheme.) A callout from Theoi Online notes:
“Boreas, the North Wind, is depicted with shaggy hair and beard, with a billowing cloak and a conch shell in his hands; Notos, the South Wind, pours water from a vase; and Zephyrus, the West Wind, is shown scattering flowers”.
Above the winds, Greek inscriptions identify each by name. In fact, local tradition long called the tower the Temple of Aeolus because of its association with wind gods. (Aeolus was the mythical ruler or keeper of all winds.) The Tower of the Winds thus blends myth and meteorology: each sculpted figure not only decorates the building but literally indicates the wind to its facing side, a practical nod to sailors and farmers who relied on these directions.
Beyond mythic decoration, the Tower’s true novelty was its integrated timekeeping apparatus. It functioned essentially as a public clocktower long before mechanical clocks. On sunny days, wooden or iron gnomon rods projected shadows onto the carved sundial lines on each southern-facing side. The stone faces are inscribed with hour lines; for example, the south dial has eight segments (from early morning to late afternoon) and the east/west dials have four, matching the sun’s path. This allowed Athenians to read the hour by noting which line the shadow fell on. According to one study, “remnants of the eight sundials” are still visible on the Tower’s faces. In effect, the Tower had vertical sundials on all sides, unique in the ancient world.
Crucially, the Tower also kept time at night or on cloudy days via an internal water clock (a clepsydra). Water from the Acropolis spring (the famous Clepsydra well) was channeled through lead or ceramic pipes down into the tower. Inside, a regulated flow filled a vertical cylinder or reservoir at the core of the tower. As the water level rose, it lifted a float or gear that moved a pointer along an internally carved scale (the shadow of this pointer could be seen through small slits or open niches). In the 19th century, archaeologists found grooves in the central floor and holes in the roof for water pipes, confirming this hydraulic system. One reconstruction suggests an ingenious mechanism: Archimedes’ and Ctesibius’ earlier clock inventions were combined so that water steadily entered the tank, and an indicator (possibly a vertical rod) marked the hours.
In short, by design: sunlight for day, water for night. As Reuters reports, the clock’s “greatest mystery remains how [it] worked at night. The prominent theory is that a hydraulic mechanism powered a water clock device with water flowing from a stream on the Acropolis hill”. Paired with the weather vane and sundials, the Tower offered Athenians 24-hour time and wind-direction signals — arguably the world’s first meteorological station. (Stelios Daskalakis, the current head conservator, calls it “the world’s first weather station”.)
After the Ottoman era, the Tower’s story entered the modern scholarly age. In the 18th century the English antiquarians James Stuart and Nicholas Revett drew the first accurate plans of the Tower (published in their 1762 Antiquities of Athens). They reinforced the Western notion of the Tower as an “invention of the ancients.” Later travelers called it “Mysterious” due to the loss of its original mechanism and decorations.
Archaeologically, the key 19th-century moment was the excavation (1837–45) by the Greek Archaeological Society, which cleared centuries of debris. In 1843 Andrea Gasparini made a copperplate engraving documenting its then state. For over a century it stood open-air and largely stable; periodic restorations (1916–19, 1976) repaired cracks and missing stone.
The most recent chapter began in 2014 when the Hellenic Ministry of Culture launched a major conservation program. Scaffolding encircled the tower as specialists cleaned the marble and consolidated the structure. High-tech imaging during restoration revealed surprising details: multispectral photography uncovered traces of the original paint scheme – for example, the interior dome was vivid blue (“Egyptian Blue”) and the Doric friezes had a red-and-blue Greek key border. Conservators also discovered medieval fresco fragments (an angel and saint on horseback) hidden under later whitewash, showing that Byzantine worshipers had decorated the interior.
The Tower of the Winds is remarkable not only as a tourist landmark but as a symbol of Greek scientific heritage. Its combination of practical engineering and mythological artistry embodies the Hellenistic worldview that the cosmos (winds, time) could be measured and ordered. Scholars debate a few points: for example, the exact sequence of construction (some suggest Andronicus first built a similar octagonal sundial in Tinos before 50 BCE, prompting this Athens tower), or whether the Tower influenced later clock towers (Vitruvius’ fanciful 16th-century drawings did inspire 18th-century architects).
Conversations also continue about how the water clock worked mechanically. No traces of gears or seals survive, and accounts differ on whether the Nile or Mediterranean calendars were used (hour lengths varied seasonally in some Greek clocks). However, the existence of the Tower’s clepsydra is certain: it is recorded by Vitruvius and by Varro (who explicitly notes a water clock from the Acropolis spring). Recent attempts at reconstruction use Theodossiou’s model (water flows into a vertical well, indicated by a float).
Another scholarly point is the interpretation of its reliefs. While the eight winds panel is clear, minor discrepancies (some confused Lips vs. Argestes, for example) exist in ancient sources. But on the Tower itself, the labels under each wind deity leave little doubt about which figure is which.
Finally, the Tower is often discussed in the context of Vitruvius’ influence. His De architectura describes it, which is our chief ancient textual source. The tower’s later architectural legacy is notable: it became a popular motif in 18th–19th century neoclassical gardens and observatories (e.g. Shugborough Hall’s pair of “Tower of Winds” follies, Radcliffe Observatory in Oxford).
The Tower of the Winds stands today as a testament to ancient Greek ingenuity at the intersection of architecture, astronomy, and mythology. Its well-preserved structure – from the eight sculpted wind-gods to the weather-worn Pentelic marble – evokes the bustling Roman Agora it once served. Understanding its history and technology enriches our appreciation: it is not merely a relic, but a statement of human ambition to measure time and nature. Visiting in 2026, one can still feel the breath of Boreas on the north wall and imagine the drip of its ancient water clock. The Tower’s secrets – partly unraveled by scholars – remind us how advanced ancient Athens was, both in art and science. In short, the Tower of the Winds is a mysterious and marvelous landmark whose legacy blows onward through the ages.
