Diving at Passe en S

Passe en S is one of Mayotte's most celebrated dive sites, a channel cutting through the barrier reef on the lagoon's southern side near Kani-Keli, on Grande-Terre. The name refers to the S-shaped route the pass follows through the reef. Water flowing in and out of the lagoon creates strong currents that attract pelagic life, and divers regularly report grey reef sharks, schooling barracuda, large fish, rays and sometimes turtles along the walls. The site is mostly a drift dive, where divers are carried along the channel by the current, and it is not a beginner spot. Operators typically require experience beyond entry-level certification and assess a diver's level before taking them. Guided dives run daily from about 07:00 to 14:00, weather permitting, with boat transport from Kani-Keli or Mamoudzou. A single guided dive costs roughly 45 to 60 euros, and a full-day package costs about 90 to 120 euros. Plongée Mayotte takes bookings by phone and through its website. A session lasts two to four hours including boat time, briefing and surface interval. The best season is April to November, when the sea is calm and visibility is highest, and morning dives are usually smoother. Divers should follow the guide closely, carry a surface marker buoy as advised, and maintain buoyancy to avoid damaging the coral. Underwater photographers need to manage the current, so compact cameras with wrist straps are practical. Crowds are limited by the small number of operators and boats, though peak holidays are busier, and booking ahead is advised.