Thailand's Premier Marine National Park Boasts 11 Islands And Unmatched Scuba Diving In A Tropical Haven

Thailand is home to many vibrant coastal ecosystems (like those at Khao Sam Roi Yot National Park), but nothing compares to Similan Islands Marine National Park. With waters at an average temperature of 77 degrees Fahrenheit, crystal-clear underwater visibility, and an ocean full of diverse marine life and colorful-hued coral reefs, the national park attracts divers from all over the world. This destination is a cluster of 11 small islands and named after the Malay word for nine (the park's original number of islands before two more were added later).

The easiest way to get to the islands is by flying from Bangkok to Phuket on one of the local budget airlines like Thai AirAsia. From Phuket, you can take a van or bus to Khao Lak to reach the main pier, Thap Lamu. Day trips and overnight boat tours can be booked with tour operators in either Phuket or Khao Lak.

Similan National Park is among the best places to plan the perfect snorkeling vacation. On the eastern shores of Koh Tachai, if you're lucky, you'll encounter leopard sharks and manta rays. If you have a PADI Advanced Open Water Diver, you can visit the southern part of the island to see whale sharks and barracudas. Visitors can also see manta rays year-round on Koh Bon island. Home to the Pinnacle City, Koh Bon showcases roughly 82-foot-long pinnacles emerging from the sea floor. 

Koh Similan's Elephant Rock is one of the most popular diving spots in the national park, known for its challenging currents, passageways, and whale sharks. Koh Ha's deep-dive spot, Anita's Reef, boasts an array of marine life, from coral reefs to coral-dwelling fish like clown triggerfish, lionfish, and garden eels. Since the national park is a protected area, it's crucial to know how to enjoy snorkeling and diving without causing damage to marine life.

To explore the islands, you must book a day trip tour or live-aboard boat. Live-aboard boats allow you to stay overnight in one of the boat's cabins and have access to dives over multiple days. Day trips start at $78 per person and include a guide, snorkeling gear, hotel transfers to and from Khao Lak, and a buffet lunch. Diving tours typically cost more, but they also include access to more remote dive sites like Christmas Point and the famed Andaman Reef. There's a range to fit every budget, from affordable live-aboards starting at about $150 a day to luxury boats at $480 a day. To participate in either a day trip or live-aboard boat, a valid scuba diving certificate is required. Plan your trip accordingly; the national park is open from mid-October to mid-May and closed the rest of the year due to conservation efforts and monsoon season.

The islands offer more than just water activities. On the largest island, Koh Similan (aka island #8), there are a few nature trails to explore. Visit the island's west side for a hike to Donald Duck Bay, home to the uniquely shaped Donald Duck look-a-like rock above the water. Another short hike goes from Nguang Chang Bay to Horseshoe Bay. It spans 1.5 miles, leads to an abandoned Thai Navy lighthouse, and features panoramic views of the islands.

Currently, there are no bungalows or camping sites available on the islands for overnight stays. Today, the only lodging options are multi-day trips aboard live-aboard ships or accommodations on the mainland. Many travelers stay in Khao Lak, as you can take a boat from the main pier (Thap Lamu) to the Similan Islands in about an hour. There's a wide range of lodging options in Khao Lak, from high-end resorts to mid-range hotels and budget-friendly hostels.

Once you depart the pier, there are no kiosks or food stands on the islands, so it's imperative that you pack what you might need during the day. Be sure to pack reef-safe sunscreen (think twice about using basic sunscreen), motion sickness tablets, dry bags, a reusable water bottle, and snacks. However, single-use plastics are not allowed in Thailand's national parks, so avoid bringing plastic-packaged food or plastic cutlery. Flip-flops are good for the shores, but bring closed-toe shoes for hiking the trails.