AMAGISAN MARU - Chuuk (Truk) Lagoon

The Amagisan Maru holds a special place for us in Chuuk. This 138-meter tanker, settled upright at 45 meters, is an exercise in scale. We love exploring her enormous engine room, the massive pistons and crankshaft still surprisingly intact, a testament to the engineering of the time. You’ll feel a cool thermocline as you descend past the superstructure, often with schools of trevally circling the mast. Entry to the various holds is easy, revealing stacks of oil drums, and sometimes a few sake bottles scattered amongst the debris. The stern offers a fantastic swim-through into the propeller shaft tunnel, dark and narrow, but well worth the effort for the eerie silence it holds. Keep an eye out for nudibranchs clinging to the metalwork, their vibrant colours a stark contrast to the rust. This site suits experienced divers comfortable with depth and overhead environments, offering a tangible link to history.

Location
Chuuk (Truk) Lagoon, Micronesia, Central & South Pacific
Coordinates
7.287778, 151.863330
Type
wreck
Maximum Depth
45m

Wreck History - AMAGISAN MARU

Year Sunk
1944
Vessel Type
cargo ship
Cause
warfare

The Amagisan Maru was a passenger-cargo ship built in 1933 for the Mitsui Bussan Kaisha line. Like many civilian vessels, she was requisitioned for service with the Imperial Japanese Navy during World War II. Her fate was sealed when she was caught at anchor in Truk Lagoon, a major Japanese naval base in the Central Pacific, during a massive U.S. Navy attack.

On February 17, 1944, Operation Hailstone commenced. It was a devastating two-day air and surface assault that caught the Japanese forces by surprise. Carrier-based aircraft from Task Force 58 swarmed the lagoon, sinking over 40 ships and destroying hundreds of aircraft. The Amagisan Maru was one of the many victims, hit by bombs and sent to the bottom of the lagoon where she has remained ever since.

Today, the Amagisan Maru is a premier wreck dive for advanced and technical divers. She sits upright in approximately 45 metres of water, with her deck accessible to those with deep-diving qualifications. The wreck is largely intact, and divers can explore her holds, which still contain items like tanker trucks and other war materials. The bridge and engine room offer fantastic penetration opportunities for the properly trained. As with all the wrecks in Truk Lagoon, she is now a vibrant artificial reef, covered in coral and teeming with marine life, serving as both a war grave and a spectacular underwater museum.

Best Time to Dive in Chuuk (Truk) Lagoon

The warmest water temperatures in Chuuk (Truk) Lagoon occur in January, averaging 28.9°C. The coolest conditions are in December at 28.9°C.

Monthly Water Temperatures

  • January: 28.9°C (air: 27.8°C)
  • February: 28.9°C (air: 27.7°C)
  • March: 28.9°C (air: 27.5°C)
  • April: 28.9°C (air: 27.5°C)
  • May: 28.9°C (air: 27.7°C)
  • June: 28.9°C (air: 27.5°C)
  • July: 28.9°C (air: 27.5°C)
  • August: 28.9°C (air: 27.7°C)
  • September: 28.9°C (air: 27.7°C)
  • October: 28.9°C (air: 27.9°C)
  • November: 28.9°C (air: 27.9°C)
  • December: 28.9°C (air: 27.9°C)

Nearby Dive Sites in Chuuk (Truk) Lagoon

Nearest Dive Centres to AMAGISAN MARU

Marine Life in Chuuk (Truk) Lagoon

Home to 213 recorded species including 133 reef fish, 36 hard corals, 17 sea cucumbers, 12 sea snails & nudibranchs, 5 sharks & rays, 4 clams & mussels.

Notable Species

Recommended Packing List for AMAGISAN MARU

Based on average water temperature of 28.9°C.

  • 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