
The Blue Dolphin
Big Blue are the proud operators of the Blue Dolphin; a Similan Islands diving Speedboat designed by divers for divers. The Blue Dolphin is the most convenient way to see the Similan Islands. Get to Thailand’s best dive sites in only 1 hour.
The interior of the Blue Dolphin was designed by us. The design maximises space and comfort, whilst also having a large tank rack and custom built dive platform. It was built, and is regularly maintained, by a local speedboat company. This is a Similan Islands diving day trip boat built specifically for divers.
Length: 14.3m/47ft
Enigines: 3x 250HP Honda 4 stroke
Speed: Cruising speed 30kts. Top speed 40kts+
Capacity: 17 guests maximum
Features: GPS, radio, toilet, shower, emergency oxygen, first aid kit, tank rack, spare diving equipment and camera bucket
Similan Islands Diving Packages
Choose between the Similan Islands, Koh Bon, Koh Tachai or Richelieu Rock.
3 day trips: 16,900฿
6 dives. Save up to 2,000B
4 day trips: 22,200฿
8 dives. Save up to 3,000฿
5 day trips: 26,500฿
10 dives. Save up to 5,000฿
Includes equipment and marine park fees.
If you have your own diving equipment then contact us to save even more.

Our exclusive packages offer the best value Similan Diving
Weekly Schedule
Depending on the location of your hotel, you will be picked up some time between 07:30 and 08:30. If you would like advice on the best hotels around Khao Lak then please contact us for more information.
The Blue Dolphin departs at 09:00. All our Similan Islands diving day trips include 2 dives. Depending on sea conditions and which dive site we are going to, it is a journey of between 50 and 75 minutes. Enjoy a delicious home-cooked Thai style buffet lunch after the first dive. Dive 2 will be after the surface interval and then head back to the pier to fill in your logbooks. Be back in time for sunset on the beach. The Blue Dolphin is the fastest and most convenient way to experience Similan Islands diving.
Mon: Koh Bon & Koh Tachai 4900฿
Tue: Richelieu Rock 5100฿
Wed: Similan Islands 4700฿
Thu: Richelieu Rock 5100฿
Fri: Koh Bon 4700฿
Sat: Richelieu Rock 5100฿
Sun: Surin & Richelieu 5100฿
Marine Park Fees: +700฿
MPF are paid daily. Discounts available for Thai Nationals.
Equipment Rental: +500฿
Daily rate for full set. Price includes regularly serviced BCD, Reg, Mask, Fins and Wetsuit. Discount for own equipment.
Included
- Experienced dive guide
- Taxi to and from private pier
- Water and Soft Drinks
- Lunch and fresh fruits
- Tanks and weights
Not Included
- Personal diving insurance: 250฿
- Nitrox: 150฿ (per tank)
- Underwater camera: 1000฿
- Dive computer: 250฿
- Private guide: 1500฿
Maximum of 4 divers per guide. We will always do our very best to put divers of a similar experience level together.
If the Blue Dolphin schedule does not work for you, we offer Similan Island Diving and Snorkeling every day of the week with our Khao Lak partners. We also offer half-day, 2 dive trips to the Boon Sung Wreck for only 3200฿ (all included).
Similan Islands Diving
The Amazing Richelieu Rock every day of the week
Richelieu Rock may be the best dive site in Thailand, but there are many other great options for Similan Islands diving.
Have your chance to fly with beautiful Giant Manta Ray’s at Koh Bon.
Current at Koh Tachai can be a little challenging, but this attracts lots of big fish.
Find out more about all the wonderful dive sites of the Similan Islands.
Similan Islands Diving Bookings

Did You Know?
Most day trip diving boats do not go to the incredible Richelieu Rock.
Often considered Thailand’s best dive site, it is simply too far for most boats.
Don’t worry, we go 4 times a week (and can organise on other days also)!
What else would you like to know?

Day Trip Diving
What do I need to bring?
We are on hand to answer any questions you have about our Similan Islands diving day trips.
However, to make things even easier, take a look at our detailed guide to help plan your day.
Similan Islands
The Similan Islands National Marine Park lies directly west of the Thai mainland, making Khao Lak a great starting point for your trip. Each island is surrounded by thriving coral reef, starting in the shallows just a few metres from the beach.
Diving in the Similan Islands allows you to experience a large variety of dive sites. From rocky canyons and swim through’s to stunning coral gardens. From huge granite boulders to limestone ridges and walls.
A little north of the Similan Islands, but still part of the same marine park, lies Koh Bon and Koh Tachai, stand alone islands with fantastic diving opportunities.
Koh Bon features a long sloping reef with cleaning stations favoured by large Manta Ray’s flying by. Although cleaning and feeding are still possible options, current research suggests that these types of locations are actually socialising sites for the Manta Rays.
Even further North is the island of Koh Tachai. On the south side of the island lies Koh Tachai pinnacle. A dive site with sometimes strong currents but worth visiting for the great coral, resident leopard sharks and large schools of feeding fish.

Similan Islands Snorkeling
Snorkelers are welcome on our Similan Islands diving trips, however the Blue Dolphin is primarily a diving boat. Other dedicated service providers offer amazing trips to stunning, healthy and shallow snorkeling locations. Did you know the Surin Islands offer far superior snorkeling sites than the Similans? Email us for more advice on snorkeling.

Surin Islands
Further north of the Similans, you will find the Surin Islands. East of these islands, and part of the Surin National Park, lies a rock. At high tide this rock is fully submerged and at low tide you can just see it poking above the surface. Its name is Richelieu Rock, and it is probably the best dive site in Thailand.
Even its name has an interesting story. Legend tells that it was named by Jacques Cousteau, the inventor of Scuba diving. Yet history suggests it was actually named after a Danish entrepreneur who became the only ever commander-in-chief of the Thai Royal Navy.
Richelieu Rock is a dramatic series of rocks in a rough horseshoe shape that features the best chance for whale sharks and also stunning macro-life. Look out for ornate ghost pipefish, tigertail seahorses, harlequin shrimp and many other goodies. The macro photographers “wet” dream.
Frequent schools of barracuda, mating cuttlefish and various other pelagic fish round off a site that never ceases to amaze. If you only do one dive in Thailand, it should be Richelieu Rock.