Hin Daeng

Hin Daeng, the Red Rock, is one of those Thai pinnacles that divers talk about in a slightly lower voice. Rising from deep water in the Andaman Sea roughly halfway between the Phi Phi islands and Koh Lanta, the summit breaks the surface at a single exposed rock, and the structure drops away quickly on every side. The upper reaches are in the 15 to 20 metre range, and the reliable diving for most teams happens between 18 and 30 metres along the western and southern walls where soft corals in every shade of pink, red and purple drape the rock face. Advanced Open Water is the honest baseline because of the depth, the current and the exposed location. The site is a current magnet. Cold upwellings sweep in from the deep water around the pinnacle, and the plan often changes mid briefing to pick the sheltered side of the day. When the current runs you hold the rock with a fist in the sand or on a bare patch, and watch the parade come to you rather than the other way round. That is when Hin Daeng delivers what it is famous for. Giant manta rays visit the cleaning stations on the wall, most often from late December through April. Whale sharks pass through in the same window, usually in small numbers but unmistakable when they do. Schooling trevallies, barracuda, and chevron barracuda move in tight silver sheets through the blue. The site pairs naturally with Hin Muang, the Purple Rock, a ten minute boat ride away and marginally deeper. Most day boats run the pair as a two tank trip out of Koh Lanta, and liveaboards working the Similan to Phi Phi corridor will slot both into an afternoon. Conditions are at their most workable from November through April. Outside of that window the Andaman monsoon closes access, and Hin Daeng simply stops being a sensible plan.