Marais is the gay centre to Paris. The place where most of the bars and pubs are for an evening out. There are also numeorous eateries to enjoy.
Culture
It has a relaxed atmosphere and similar to most large European cities it is extremely gay friendly. It is not as overtly gay as Berlin or London but it can certainly be identified as you approach the vacinity.
Travel Information
Easy to get to by bike or metro. Being extremely central it is reasonably easy to find - just look out for the art gallery of a former president ;-)