Key West is a gay sauna on rue La Fayette in the 10th, between Gare du Nord and Poissonniere. It was renovated recently and the interior is modern rather than the worn-in look most Paris saunas have.
The layout has a sauna, a hammam, a jacuzzi, a fitness area, playrooms, private cabins, chill zones, a smoking area and a bar with snacks. WiFi runs throughout.
It programmes themed evenings through the week. Being outside the Marais it draws more of a local crowd than the central saunas do.