The "S" pass is a reef pass that cuts through the eastern arc of the Mayotte outer coral reef. It is characterized by its singular shape of inverted "S" (or rounded "Z"). It is one of the twelve passes of the Mayotte outer barrier1, and its maximum depth seems to be 65 metres2.

 

This pass originated from the bed of an old river dating back to the time when, since sea level was much lower, the island of Mayotte extended to the present external barrier3. With the rise of the waters (and the erosion of the island) between 7,000 and 3,000 years ago, accompanied by the rise of the coral reef, this structure has been preserved as water continues to flow through it for filling and emptying the lagoon due to the tides. It is therefore a privileged site for "drifting" dives.

 

Easily accessible from Mamoudzou or Petite-Terre (5 miles2), this pass is one of the most famous scuba diving sites in Mayotte, offering a wide range of depths and underwater landscapes, and allowing the observation of rare species such as the Napoleon, large rays, marine turtles or even dugongs.

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