The Mayotte Lagoon is the centerpiece of the island — a vast enclosed sea covering more than 1,000 square kilometers, protected by a barrier reef over 160 kilometers long. The water inside is calm, clear, and astonishingly rich in marine life: sea turtles, eagle rays, dolphins, and dense reef fish in every direction.
From July to October, humpback whales enter the lagoon to calve, and boat operators run morning tours that put you in the water alongside whale mothers and their calves in water rarely more than a few meters deep. This is one of the few places in the world where this is reliably possible. The best operators are based at the Plage de N'Gouja on Grande-Terre, where turtles also come ashore to lay eggs.