Richelieu Rock is a limestone pinnacle in the Andaman Sea within Mu Koh Surin National Marine Park, accessible only by boat from Khao Lak, roughly forty-five kilometres away. The site rises to the surface only at low tide and drops to thirty-five metres, with reef and wall topography suited to intermediate and advanced divers. Currents can be moderate, and visibility spans a wide range depending on conditions. The region also includes two decommissioned naval vessels, the HTMS Phratong and HTMS Phra Thong, both serving as artificial reefs at moderate depths. Species recorded across these sites include whale shark, green sea turtle, harlequin shrimp, common seahorse, and painted frogfish.
Monthly water temperature across Richelieu Rock's sites, from satellite sea-surface data corrected for depth. The band shows the site-to-site spread.
Water is warmest from May through August and cools slightly from November into early January, though it remains comfortable year-round. The season for accessing these remote sites runs from mid-October to mid-May, as the southwest monsoon closes the area to boat traffic for the intervening months.
1 operator
Water temperature around Richelieu Rock ranges from about 27°C in November to 30°C in May, based on satellite sea-temperature data for its dive sites.
With water around 27–30°C, a rash guard or 3mm shorty works in Richelieu Rock year-round.
Fin maps 3 sites in Richelieu Rock (3 scuba diving sites).
Across Richelieu Rock's dive sites, February, April, May and November are most often reported as the best months to visit.
2 more sites to explore
