Bon Soong Wreck - Similan Islands

The Bon Soong Wreck is one of our favourite dives in the Similans, especially if you’re a fan of something a bit different from the usual granite boulder landscapes. This old tin dredger, sunk intentionally in 1984, sits upright and largely intact, inviting exploration. We love dropping down onto the main deck, often finding a leopard shark or two resting on the sand nearby, completely unbothered by divers. Inside, we’ve often seen schools of fusiliers so thick they block out the ambient light filtering through the open hatches. You can navigate through the holds and engine room, where the light changes dramatically as you move from one section to another. Look closely at the superstructure; it's colonised by soft corals, and we’ve spotted ornate ghost pipefish camouflaged amongst them more than once. The wreck typically sits in good visibility, but there can be a slight current, so it’s best for divers comfortable with basic wreck penetration and drift conditions. We'd suggest going in the morning; the light seems to hit it just right.

Location
Similan Islands, Thailand, Southeast Asia
Coordinates
8.773796, 98.163185
Type
wreck

Wreck History - Bon Soong Wreck

Year Sunk
1984
Vessel Type
cargo ship
Cause
unknown

Before it was one of Thailand's most famous dive sites, the Bon Soong was a tin dredger, a hard-working vessel in the region's once-thriving mining industry. In 1984, its industrial life came to an end when it sank off the coast of Khao Lak. While the official cause is not widely known, local dive lore often suggests everything from a navigation error to more colourful, unconfirmed tales. Twenty years later, the powerful 2004 tsunami further impacted the site, breaking the vessel into several distinct sections and scattering its components across the sandy bottom.

For divers, the Bon Soong Wreck is legendary, often described as 'fish soup' due to the sheer density of marine life it attracts. Lying on a sandy bottom at around 18 metres, the wreckage acts as a magnet for vast, swirling schools of snapper, fusiliers, and trevally. The structure itself is an encrusted wonderland, providing a habitat for countless creatures. Divers can spend their entire dive exploring the nooks and crannies, searching for ornate ghost pipefish, colourful nudibranchs, stonefish, and moray eels of all sizes. It is an absolute must-do dive for anyone visiting the Khao Lak area, promising an unforgettable underwater spectacle.

Marine Protected Area: Khao Lak - Lam Ru

Best Time to Dive in Similan Islands

The warmest water temperatures in Similan Islands occur in May, averaging 30.8°C. The coolest conditions are in January at 28.6°C.

Monthly Water Temperatures

  • January: 28.6°C
  • February: 29.0°C
  • March: 29.6°C
  • April: 30.6°C
  • May: 30.8°C
  • June: 29.9°C
  • July: 29.6°C
  • August: 29.3°C
  • September: 29.0°C
  • October: 29.0°C
  • November: 29.2°C
  • December: 28.7°C

Nearby Dive Sites in Similan Islands

Nearest Dive Centres to Bon Soong Wreck

Marine Life in Similan Islands

Home to 183 recorded species including 127 reef fish, 38 hard corals, 9 seagrass & algae, 4 sharks & rays, 2 other, 1 octopus & squid.

Notable Species

Recommended Packing List for Bon Soong Wreck

Based on average water temperature of 29.4°C, currents 7 cm/s.

  • Shorty or Rashguard - warm 29°C water needs minimal exposure protection
  • Mask - essential for every dive
  • Fins
  • BCD - buoyancy compensator
  • Regulator - your most safety-critical piece of gear
  • Dive Computer - tracks depth, time, and NDL
  • Surface Marker Buoy (SMB) - essential for boat pickups
  • Dive Torch - useful for crevices and colour at depth
  • Underwater Camera - capture your diving memories