L'Atlantis is the sauna most people mean when they talk about the La Rochelle sauna, although it stands just outside the city, in the Belle Aire industrial estate at Aytré. A city bus runs out to it.
The building is 260 square metres over two floors with a terrace on top, air conditioned throughout. There is a Finnish sauna, a hammam and a spa, a bar serving alcohol and something to eat, a small shop, video lounges and a massage room you book at reception. The play areas run to a backroom, a sling and glory holes, with cabins to lie down in. Condoms and lubricant are laid out for the taking.
Part of the week is men only, including a naturist session, and the rest is mixed libertine, so it pays to know which one you are walking into. The place is newer and better kept than an industrial-estate address would lead you to expect.