Completely different from the Similan Islands, here you will find a line running west from the island. The ridge is covered with small soft corals and surrounded by a mixture of hard and soft coral. This site is found on the under sea extension of the islands west ridge which drops sharply to about 40 meters before the sea floor, slopes away to greater depths.

Large schools of fusiliers, snappers and travellies are also very common here. Also commonly seen here are leopard sharks, white tip reef sharks, and manta rays.

Aside from the astounding reef life, Koh Bon is one of the best places to see big pelagic creatures; both giant Mantas and Whale Sharks are local residents here. Leopard Sharks, Reef Sharks and large Stingrays also make their appearances. When visibility is at its peak, this site is reminiscent of diving inside the grand canyon. The shear magnitude of this place is amazing.

Hard corals extend down to about 25 meters, while giant sea fans are found from 18-40 meters. These sea fans which are pastel in color are perhaps the most beautifully colored of all the sea fan corals found in Thailand. Large barrel sponges also grow along the ridge.