Sitting just a couple of hundred metres next to the well-known Hin Daeng is Hin Muang (Purple Rock in the local language). Nobody is really sure why these two undersea pinnacles are referred to as a pair and called ‘Hin Daeng’ because neither is better than the other.
Maybe it’s just that Hin Daeng is easier to pronounce than Hin Muang, especially for foreigners. The two dive sites are right next to each other, and very similar in their topography and the marine life there. It is claimed that Hin Muang has more purple soft corals than red, when compared to Hin Daeng. Hin Muang’s pinnacle can be seen above the water’s surface at low tide, but there is no opportunity to do anything here, such as relax on a beach. It literally is a bit of rock sticking a metre or two out of the water and hardly big enough to notice. What lies underneath is very different, though.
Hin Muang is home to the deepest and steepest drop-off wall in all of Thailand. It really is something that needs to be seen to be understood. The wall continues down into the dark depths of the sea. Experienced technical divers are able to descend to 70 metres, but of course most divers are limited to 30 or 40 metres. Those who are lucky enough to go diving at Hin Muang are guaranteed to see one of Thailand’s best dive sites. In fact, on its day it can be the best. It just depends on the sea & weather conditions, the marine life seen and how many other divers are there at the same time.
Because Hin Muang is a submerged pinnacle in very deep sea far from the nearest island and even further from the mainland, it is exposed. This means that surface waves can be an issue because there is no landmass to offer shelter from wind or the waves. Also, there’s nowhere for the dive boats to get protection, so things can be a bit rocky on some days. The good news is that the depth and distance from everywhere else means that the water is usually very clear. Divers at Hin Muang can expect 20-30 metres visibility during the diving season. Currents can be an issue, but with a good dive plan, it’s normally ok. Divers can get shelter from the currents, or change the dive order, and visit Hin Daeng instead.
This is something that makes Hin Muang arguably the best dive site in Thailand. Not only is it large, deep and right next to Hin Daeng, not many day trip or liveaboard diving boats visit this location. Therefore, the dive site is rarely crowded. It’s quite common for a dive boat to be the only one at Hin Muang & Hin Daeng, and even if there are two or more diving boats there, they can easily manage the dive timing and which of these great dive sites are visited in which order.
Officially, Koh Haa National Marine Park (in which Hin Muang is located) opens each year on October 15th and closes on May 15th. However, due to the location far from land, the conditions can be unpredictable. Therefore, diving takes place from November to April, with the best months being December to March.
Hin Muang is a limestone underwater pinnacle in open sea, surrounded by water that is 70 metres deep or more. Therefore, the surface can be rough and currents are often present. It's covered in plenty of hard & soft corals, which attracts a huge amount of marine life.
Hin Muang is just 200 metres from Hin Daeng, its sister dive site. They are at least 60 km. from Thailand's mainland, with the nearest province being Trang. The nearest island is Koh Rok, which is almost half way (25km) from Hin Muang to the mainland. 60 km north from Hin Muang is Koh Phi Phi, and Phuket is 90 km to the northwest.
Although day trips are possible to Hin Muang, it's not practical, and it's expensive. By far the best way to get to Hin Muang is on a scuba diving liveaboard cruise (diving safari). These leave from Phuket and travel through the night so you wake up ready to dive.
There are no official regulations forbidding inexperienced divers from Hin Muang, but in reality, you need to be Advanced or Open Water with a 30m (99ft) Deep Dive certification. It's also necessary to be comfortable in a current, and with waves at the surface.
Almost anything can be seen when scuba diving at Hin Muang. This includes bony & cartilaginous fish, invertebrates and reptiles. Some divers who are able and prepared to go very deep at Hin Muang report several shark species which are not normally seen by divers in Thailand. The wall is covered in soft corals, which are home to many interesting critters. And every diver at Hin Muang hopes to be lucky enough to spot a visiting Manta Ray or passing Whale Shark, but these can never be guaranteed.
On a good day, Hin Muang is the best dive site in Thailand! It is rarely busy with other divers, which means shy species aren't scared off. Plus for most of us, a tourist attraction is better enjoyed when not busy. With or without lots of other divers, the topography, clear water and marine life ensure a great dive every time. It has a steep & deep (70m.) wall, a vast amount of marine life, and large pelagic visitors are often seen. Surface waves and currents can be an issue, but your divemaster guide will plan and lead the dive so that everyone enjoys as long & safe dive as possible.