Australian, British, Canadian, US, and EU citizens do not need visas for a trip to French Guiana as a tourist and providing you have proof of a return ticket, you can stay in the territory for up to three months. You must possess yellow fever vaccination certificate and your passport must be valid for at least three months post-travel. No other shots are required, athough protection against endemic diseases is always ideal.
The dominant religion of French Guiana is Roman Catholicism; the Maroons and some Amerindian people maintain their own religions. The Hmong people are also mainly Catholic owing to the influence of missionaries who helped bring them to French Guiana.
If you are planning to visit the French Guiana, you should definitely know something about its weather. That way you will have the appropriate clothing.