Koh Bon West Ridge
Koh Bon is a small limestone island north-west of the main Similan chain, part of the same national park. Its west ridge drops from about 10–15 m to beyond 35 m and works as a cleaning station: manta rays visit regularly, often at the start of the incoming tide, and circle slowly over the ridge. Napoleon wrasse, blacktip reef sharks and eagle rays are common, and leopard sharks rest on the sand near the base. The ridge is covered in small yellow soft corals.
depth: 10–40 m