Diving & Snorkelling
The Similans offer diving for all levels, at depths from 2m to 30m. There are rock reefs at Ko Hin Pousar and dive-throughs at Hin Pousar, with marine life ranging from tiny plume worms and soft corals to schooling fish, manta rays and rare whale sharks. Ko Bon and Ko Tachai are two of the better diving and snorkelling areas. There are dive sites at each of the six islands north of Ko Miang. The park's southern section (Islands 1, 2 and 3) is an off-limits turtle nesting ground.
No facilities for divers exist in the national park, so you’ll be taking a dive tour. Dive schools in Hat Khao Lak book day trips (two dives 6000B) and liveaboards (three-/six-day trip from around 19,000/35,000B), as do Phuket dive centres (two-dive day trip from 5600B, three-day liveaboard from 18,900B).
Agencies in Khao Lak offer snorkelling-only day trips that visit three or four sites from 3200B.
Wildlife & Hiking
The forest around Ko Miang's visitors centre has some walking trails and great wildlife. The fabulous Nicobar pigeon, with its wild mane of grey-green feathers, is common here. It’s one of the park's 39 bird species. Hairy-legged land crabs and fruit bats (flying foxes) are relatively easy to spot in the forest, as are flying squirrels.
A small beach track, with information panels, leads 400m east from the visitors centre to a tiny snorkelling bay. Detouring from the track, the Viewpoint Trail, about 500m or 30 minutes of steep scrambling, has panoramic vistas from the top. A 500m (20-minute) walk west from the visitors centre leads through forest to smooth west-facing granite platform Sunset Point.
The only accommodation in the Similans are 20 simple (and over-priced) bungalows on Ko Miang, a neighbouring campsite (tents provided) and another campsite on Ko Similan. You will need to book at least two to three months ahead to guarantee a bed or a tent.
A restaurant beside the park office on Ko Miang serves simple Thai food. There's another one on Ko Similan for those staying the night.