West Ridge

West Ridge is a deep vertical wall on the western face of Sipadan Island, in the Celebes Sea. The reef drops sheer from the surface to 40 m and beyond, rising from an extinct volcanic seamount that climbs 600 m from the seabed. The rock face is characterised by pronounced ledges and deep structural crevices, with robust black coral bushes anchoring themselves to the wall through its deeper sections. Divers typically work a depth range of 18–40 m, with an average around 20 m, and conduct their safety stop in open water alongside the wall, as there is no shallow reef flat.

The wall holds large resident groupers and Napoleon wrasse patrolling its full length, while green and hawksbill turtles feed actively along the structure, audibly crunching coral as they go. Anemonefish and sweetlips populate the shallower sections encountered on the ascent.

West Ridge is best dived in the afternoon, when the descending sun illuminates the wall directly from the west, bringing out the textures of the reef and lighting the deeper crevices. Visibility reaches up to 30 m. The best conditions run from March to October, with water temperatures between 26–30 °C. Current is a moderate drift, generally calmer than the high-energy flows at Sipadan's northern points, though it requires active finning at times. Sipadan is closed to all visitors every November for marine conservation.