The park covers 140 square kilometres in total, 14 of those being land in the shape of an archipelago consisting of nine islands. They are Ko Bon, Ko Bayu, Ko Similan, Ko Payu, Ko Miang (two adjoining islands), Ko Payan, Ko Payang, and Ko Huyong. For simplicity they are often referred to by their number instead - 1 through 9 starting from the south. Recently, the park was expanded to include the two remote islands Ko Bon and Ko Tachai, but since "Sembilan" is Malay for "nine" this doesn't seem to stick in people's minds and those are not visited as often as the original nine.
The islands were created by upwellings of hot magma during the Tertiary-Cretaceous period some 65 million years ago, then smoothed by glacial ice and the erosion by the sea. The coral reefs are about 5,000 years old and hence the oldest in Thailand. In 1982, the national park was established and now it is scheduled to become a UNESCO World Heritage Site.
The 2004 tsunami left the islands and the underwater landscape almost unharmed, since the waters are very deep around the islands.
The nine granite islands are postcard perfect images of paradise, covered in tropical jungle and equipped with beaches of chalk-white sand. As if this was not enough, the views under the water surface are even more impressive and many people believe this is the best dive site in Thailand. Skin-Diver Magazine has acclaimed the Similans to be one of the ten most beautiful places in the world.
Flora and fauna
There is an enormous diversity of fish species. Underwater visibility is the best you will find in Thailand. You will see plenty of colourful fish such as lionfish and clownfish (Nemo), and if you're lucky you may spot a bigger one like a manta or even a whale shark. The corals in the area have largely fallen victim to coral bleaching in 2010 and have not yet recovered, though the fish still make snorkelling and diving worthwhile.
On Ko Huyong, the Royal Thai Marines run a turtle breeding facility and access to the island is restricted.
High season in the Similans is from Dec-Apr, when the monsoon stays far away. The best period to visit is Mar, when the winds are calm and the water clear. The national park is closed from 16 May-15 Nov.
There are several dive trips going to the Similans from Phuket, Khao Lak, and Ranong. Both day trips and liveaboard cruises are available. Dedicated cruises usually start at 4 days and 4 nights (4d/4n) in length. Many shorter trips are available, often with operators who have a large vessel stationed at the islands who do regular transfers using speed boats.
There is a national park entry fee of 400 baht per traveller and a further daily usage fee of 200 baht per diver per day. Most boats do not include this in their quoted price. It is paid to your dive operator before the trip.
Some diving liveaboard trips depart from Chalong or Patong. Most departures actually leave from Tap Lamu near Khao Lak but focus on the Phuket area, with offices in Phuket and pickups from major beaches. Map Similan islands dive sites
Diving liveaboards and dive trips
- Dive Asia, 24 Karon Rd, Kata Beach, Phuket, ☎ +66 76 330598, +66 76 284117, fax: +66 76 521949, e-mail: email@example.com. Scuba diving and snorkelling trips. Similan liveaboard trip, Richelieu Rock, Surin Islands. PADI course, dive equipment sales and rentals.
- Jonathan Cruiser, 43/63 Moo 5, Viset Rd, Rawai, Phuket, ☎ , fax: +66 76 281530, e-mail: firstname.lastname@example.org. Offers 4 day/5 night and 5 day/6 night liveaboard diving trips. 25,000 baht for 4 days/5 nights plus park fees and rental.
- Peterpan Andaman Diving Co., Ltd., 8/62-3 Moo 3 Kwang Rd. Vichit Rd, Phuket, ☎ +66 76 521948, +66 76 521949, fax: +66 76 521949, e-mail: email@example.com. Scuba diving and snorkelling trips, Richelieu Rock daily trip, Surin Island daily trip, liveaboard trip to Burma (Myanmar) liveaboard trip to Similan Islands. Private charter cruises. PADI course, dive equipment rentals.
- Phuket Scuba Club, 241 Koktanod Rd, Kata Beach, Phuket (opposite Mom Tris Boathouse Hotel), ☎ , fax: +66 76 284026, e-mail: firstname.lastname@example.org. Regular liveaboard departures from Phuket available Oct-May high season.
- Scuba Cat Diving, 94 Thaweewong Rd, Patong, Phuket, ☎ , fax: +66 76 293122, e-mail: email@example.com. Several liveaboard options are available. 3 cruise vessels do longer trips (4 days/4 nights and up) to the Similan Islands and other destinations. The MV Scuba Cat is moored at the Similans throughout the high season with transfers by speedboat on Su, M, W and F. 2 day/1 night or extended stays are available. The lack of daily transfers has its upside: there is not the bustle of divers arriving and leaving every single day. From 12,000 baht for 2 days/1 night.
- South Siam Divers, 459/1 The Best Villa, Patak Rd, Karon, Phuket, ☎ , fax: +66 76 286020, e-mail: firstname.lastname@example.org. South Siam Divers has two boats moored at the Similan Islands, one with daily transfers and one with transfers 5 days a week (excluding W and Su). Day trips through to living on-board for a week or more. The boat sleeps 28 and day trips are also possible, so during peak season there can be as many as 60 people on board for lunch between the arrival and departure of the speedboat. Divers are allowed 4 dives a day of 50 min each and must follow a guide. From 11,000 baht for 2 day/1 night.
- Sunrise Divers, 269/24 Patak Rd, Karon, Phuket, ☎ , fax: +66 76 286130, e-mail: email@example.com. In Phuket since 1999, offers liveaboards and day trips to the Similan Islands on a wide variety of boats from backpacker-style to more luxurious.
Diving liveaboards and dive trips
- White Manta Liveaboards, 18 Sin Ming Walk, #02-03, Singapore, ☎ , fax: +65 6452 5496, e-mail: firstname.lastname@example.org. A Singaporean operator which has two vessels doing liveaboards in the Similans on the MV White Manta and the MV Black Manta. White Manta liveaboards are fairly high-end, with the option of staying in luxury master suites with en suite baths. 4 day/3 night trips start at approximately 28,000 baht.
Diving liveaboards and dive trips
- Khao Lak Trip Dive Centre, 4/93 Moo 7, Khuk Khak, ☎ +66 76 485297, +66 84 6386668, fax: +66 76 485296, e-mail: email@example.com. 4day/4 night trip (up to 14 dives) to the Similan Islands, Ko Bon, Ko Tachai, and Richelieu Rock. From 18,900 baht.
- Manta Point Dive Center, 91 Moo 6, Khao Lak, ☎ , e-mail: firstname.lastname@example.org. Operate liveaboards to Similan Islands and Richelieu Rock from Khao Lak. Daily departures for any duration.
- Oktavia Dive Center, 70/4 Moo 5, Bang Niang (200 m past Pinocchio Restaurant towards the beach), ☎ , e-mail: email@example.com. Owners and operators of MV Oktavia, one of the largest vessels cruising the Similan Islands for divers, snorkellers, and sun-worshippers alike.
- Similan Dive Center, 22/37 Moo 4, Bang La On (across Rte 4 from Bangkok Bank), ☎ , e-mail: firstname.lastname@example.org. Open all year. Khao Lak ecological dive centre offers diving in a friendly atmosphere with an experienced crew. Day trips and daily departing liveaboards to the Similan Islands, Ko Bon, Ko Tachai and Richelieu Rock. Official Mares Dive Centre with a large range of diving and snorkeling equipment. Operated by Khao Lak residents with over 20 years of experience in environmental research and diving.
- Similan Diving Safaris, 13/19 Moo 7, Khao Lak, Khuk Khak, ☎ , fax: +66 76 485471, e-mail: email@example.com. From 17,800 baht (bunk in a 4-person room) for 4days/4 nights..
- Similan Paradive, Bang Niang, ☎ , e-mail: firstname.lastname@example.org. French dive school, PADI and CMAS. From 11,500 baht for 2 day/1 night.
- Thailand Dive & Sail (Khao Lak Dive Centre), 4/88 Soi Bang La On, Moo 7, Khuk Khak (on the side street leading to Banana Bungalows near the Viking Restaurant), ☎ , e-mail: email@example.com. Reliable, independent information and booking services for scuba diving, snorkelling and sailing trips to the Similan Islands.
- Wicked Diving (Khao Lak Diving), 4/17 Moo 7 Khao Lak (adjacent to Viking Restaurant in the heart of Khao Lak), ☎ +66 76 485868, +66 76 486868, e-mail: firstname.lastname@example.org. Khao Lak's only dive shop run to ethical and environmentally friendly standards. Operating two liveaboards offering 3 and 5 day expeditions to the Similan and Surin Islands providing for all diving skill levels. Also offer diving training, overnight tours and 3 day/2 night diving adventures with the nights spent on the the islands and days spent at various dive sites. 3day/2 night trips depart on M and F.
- Similan Tour, 1/6 Khao Lak, Lam Kaen, ☎ , e-mail: email@example.com. A snorkelling-only liveaboard for 3 days/2 nights, departing Tu and F. 7,400 baht.
- Kon-Tiki Khao Lak Diving & Snorkeling Center, 13/128 Moo 7, Khuk Khak, ☎ , fax: +66 76 485378, e-mail: firstname.lastname@example.org. Daily diving and snorkelling trips to the Similan and Surin Islands. PADI scuba diving courses and monthly IDC. Liveaboards to Similan Islands, Burma Banks, and Andaman Islands.
- Similan Scuba Adventures, 4/56 Moo 7, Khuk Khak, ☎ , fax: +66 76 485610. Day trip where divers and snorkelers go to different sites to get the most out of the experience. Have liveaboards. Day trip is 1,994 baht for snorkellers and 2,922 baht for divers (2 dives).
- Lanta Diving Safaris, 289 Moo 1, Ban Saladan, Ko Lanta, ☎ . Ko Lanta's only liveaboard, does periodic (about 1 per month) 7 day/7 night trips that include a day's diving in the Similans. 7 day/7 night trips approximately 30,000 baht plus fees.
From Ranong Province at Ranong, Ko Chang (Southern Thailand) and Ko Phayam
- Aladdin Dive Safari, Offices at Ranong, Ko Chang and Ko Payam, ☎ +66 87 2786908, +66 87 2747601. Fully inclusive dive tours featuring Ko Surin, Ko Similan, Ko Lanta, Krabi, Phang Nga, and the Mergui Archipelago in Burma (Myanmar). 14,000+ baht.
The national park admission fee is 400 baht/day (children 100 baht). For Thai citizens the fee is 40 baht, children 20 baht. A diving fee is an additional 200 baht/day regardless of passport.
There are tours leaving from Khao Lak that offer diving and snorkelling tours. Once on the islands there is the option of using the marine park boats for transit between the islands. This is not totally reliable, but is a less expensive alternative.
Incredible marine life, great scenery, white sand beaches.
The Similan Islands are home to some of the best diving sites in the world. They are also home to great snorkelling, bird watching, and sunbathing.
There are both tents and bungalows available for rent. These are only available through the national park headquarters in Tablamu or through agents.
Tents are available for rent. In addition, on Island #8 you can rent space and put up your own tent.
See the Stay safe section of the Scuba diving article for diving safety tips. The islands are closed from mid-May to early-Nov of each year. Tour operators going to the islands during the closed period are breaking the law.