Because South Sudan just recently gained independence, the immigration laws are still subject to modification. They have, however, replaced the previously utilized travel permits with appropriate visas in your passport. Visas cost USD100 and are available at all border checkpoints including Juba International Airport. The duration of the visas seems to fluctuate at random between 1 and 6 months. Depending on whatever official is at the desk on the day of your arrival, an invitation letter may be needed. The procedure may take up to three hours. If you do not have a local contact with official ties, you should get a visa before entering the nation. Visas are now available for GBP35 in cash at the embassy in London and usually take 3 working days to complete.