Saint-Georges (also known as Saint-Georges-de-l'Oyapock) is in French Guiana.
Located at the Oyapock, the border river between French Guiana and Brazil, if you travel overland between these countries you'll probably traverse this town. The town on the Brazilian side is Oiapoque. A detachment of the French Foreign Legion is stationed in the town.
The bridge across from Brazil was finished in 2011, and has opened to private vehicles in March 2017. You can probably still also cross from Oiapoque the traditional way — by boat. The crossing from Oiapoque is a 15-30 min boat ride away and cost R$15 or €5 in February 2017. Also, the boats just take a few cars and bringing a car across is expensive.
From Cayenne you can get in by bus (transfer in Régina) or car. There is an airstrip but no passenger flights.
The town is small and you can get anywhere by foot.
Fishing, kayaking and rafting in the river.
There are two hotels in the town:
Most people continue their journey either towards Cayenne by minibus €30/person (hitch hiking is possible but as the main highway only serves Saint George and the closed bridge to Brazil you may need to be patient). or across the river to Oiapoque, Brazil. Until the bridge is open, getting to the latter will involve a boat trip (€5/person). You could probably also travel upstream along the Oyapock into the rainforest.
2nd-order administrative division
Primary administrative division