Rocher du Diamant Wall

The Rocher du Diamant — Diamond Rock — is a 176-metre basalt monolith rising from the sea off Martinique's southwestern tip, commissioned as HMS Diamond Rock by the Royal Navy in 1804 and held for 17 months against French forces. The underwater wall on the western face descends from 8 metres to beyond 50, carpeted in black coral and deepwater gorgonians below 20 metres, with barrel sponges the size of bathtubs at 30 metres. Current on the open faces concentrates large pelagics: barracuda, tuna, and seasonal hammerheads cruise the structure while nurse sharks rest in the shallower caves on the calmer northern side. The four distinct faces of the rock offer markedly different ecosystems within a single boat ride.