Earlier this year, hip-hop artist Mos Def was arrested in South Africa. He was stopped trying to exit the country with a World Passport, an obscure travel document that holds little legal bearing and often represents more of a political or symbolic message of a world without borders.

While some countries will accept the document, for the most part it is viewed as a fantasy travel document and can get you in a bit of legal trouble. To learn more about the document I spoke with JustFly. An online travel agency, JustFly saw an uptick in questions about these kinds of documents over the last few months and has done their homework to find out the story behind the World Passport.

The World Passport was invented in 1954 by Garry Davis. The Founder of the World Service Authority, Davis was a stage actor and World War II Veteran who later went on to promote the idea of being a world citizen, even running in various American elections. While he died in 2013, he did receive some acclaim for offering both Julian Assange and Edward Snowden World Passports after their whistleblowing efforts got them into legal trouble. World Passports are freely available on the World Service Authority’s website, with prices starting at $45 for a three year passport.

So, what does a World Passport look like. Well, it looks like a passport, but it does have some unique features. Coming in at 42 pages, the document features writing in English, French, Russian, Spanish, Arabic, Chinese, and Esperanto. It also contains sections on medical history and organizational affiliations. Features later added include a “ghost photo”, plastic film covering, and a scannable barcode so it can be read by machines.

In terms of authenticity and its history of acceptance, it has varied over the last half century. The World Service Authority claims that the passport has, at one point, been accepted in 180 countries. This has been attributed by world governments as a mistake involving whimsical border guards and customs officials. More often than not, the user of the passport ends up being arrested. This includes Davis, who was arrested over 20 times for using his World Passport. As it stands, there are potentially seven countries that may allow a World Passport holder to enter their respective countries. This includes Burkina Faso, Ecuador, Mauritania, Tanzania, Togo, Vatican City, and Zambia.

Some notable people with World Passports according to JustFly’s review include Edward Snowden, Julian Assange, and Yasiin Bey (Mos Def). Former holders include former US President Dwight D. Eisenhower and Vaclav Havel, the last Prime Minister of Czechoslovakia.