Look for the city of Beziers on a map at the western end of the south of France. Due east is Agde and le cap d'Agde. Drive the N112 highway and take the exit south to Cap d'Agde. Keep following the signs that say "Naturist" and you will come to a dead end with a gate to the Naturist area. You will need to park here and buy a day pass. There is also parking inside which you can pay for as you buy your pass. You can also enter from the beach if you first go to the Marseillan Plage to the east, which is a different exit from the N112, but it is a long walk along the beach. You cannot get to the beach from the west because of a canal.
History/Status: Completely legitimate
Environment: A crowded festive atmosphere in the summer with mostly good weather, though not as predicably "perfect" as the Cote d'Azur.
Facilities: Just about everything. Public washrooms, restaurants at the beach, shops,
Parking: The resort area has pay-parking
Accommodation: Several resorts right there. You probably have to book many months in advance.