Koh Rok, about 25 kilometers south of Koh Ha, are two sister-islands separated by a narrow channel about 15 metres deep.
These islands, Koh Rok Nok and Koh Rok Nai (outside and inside) have some of the prettiest beaches in Thailand and are completely devoid of inhabitants.
The islands are named for a small, furry mammal called a Rok in Thai, and this animal, along with monitor lizards, can be observed on-shore with a little patience and a bit of luck.
The diving here is relatively shallow, with the best corals and fish life living above 18 meters. The bottom is composed of mostly hard corals, with small areas of soft corals at deeper depths.
Black tip sharks patrol the reef shallows and Hawks bill turtles are sighted regularly. But the main reason for stopping in Koh Rok is that it is the perfect jumping off point for trips out to Hin Daeng and the islands make an ideal anchorage in all weather.