HEIHAN MARU - Chuuk (Truk) Lagoon

The Heihan Maru, she's a big girl. At 155 metres, you’ll be doing multiple dives to properly take her in, and we think she’s absolutely worth it. What makes her a standout for us isn't just the sheer scale, it's the sheer variety. We love dropping down into the immense holds, where you can still make out the ghostly outlines of tanks and other cargo. It’s a completely different vibe from the engine room, which feels almost cathedral-like with the light shafts cutting through the gloom. You’ll find something new on every pass – a porcelain toilet still intact in the crew quarters, or a scattering of gas masks. For marine life, keep an eye on the bow and stern sections, especially around the masts. They’re usually draped in soft corals, and you’ll often find schools of fusiliers swirling so thick they practically block out the sun. It’s also a good spot for lionfish and the occasional reef shark cruising by. Our best advice? Take your time. Don't rush through; there's too much history here to just tick off the big items. Try to hit the holds around midday for the best light penetration. This is a site that truly rewards careful, repeated exploration, a must for anyone serious about wreck diving.

Location
Chuuk (Truk) Lagoon, Micronesia, Central & South Pacific
Coordinates
7.383889, 151.861390
Type
wreck
Maximum Depth
0m

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 HEIHAN 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 HEIHAN 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

Frequently Asked Questions

What is the maximum depth of the Heian Maru wreck and how shallow are its highest points?
The highest points of the Heian Maru wreck are incredibly shallow, reaching the surface at 0 meters. While the maximum depth is not specified in our current data, this substantial 155.8m long vessel offers extensive exploration opportunities. It is classified as a wreck showing any portion of its hull or superstructure.
What kind of artifacts and marine life can divers expect to see on the Heian Maru wreck?
Our current data for the Heian Maru does not specifically detail the artifacts or marine life divers can expect to encounter. However, as a former submarine vessel sunk in 1944, it holds significant historical value. Divers can explore the remains of this 155.8m long ship, which was built in 1930 by NY Osaka Iron Works.
Is the Heian Maru considered an advanced dive, or can less experienced divers explore parts of it?
The Heian Maru is classified with an intermediate difficulty rating. This means that while it offers exciting exploration for experienced divers, less experienced divers with proper training and guidance can also safely explore its shallower, more accessible sections. It is a substantial wreck, measuring 155.8m x 20.1m, providing ample opportunities for various skill levels.
What is the best time of year to dive the Heian Maru for optimal conditions and visibility?
Specific information regarding the best time of year for optimal conditions and visibility for the Heian Maru is not detailed in our current dataset. For general guidance on diving in Chuuk (Truk) Lagoon, we recommend consulting our When to Dive section. This will help you plan your trip to this historic wreck, sunk in 1944.
What scuba diving certifications are required to dive the Heian Maru, especially for wreck penetration?
Our data for the Heian Maru does not specify exact certification requirements. However, given its intermediate difficulty rating, divers should possess at least an Open Water certification. For any wreck penetration, which involves navigating inside the 155.8m long vessel, advanced wreck diving certifications are generally recommended to ensure safety and proper technique.
What are the typical current conditions and visibility like when diving the Heian Maru?
Details regarding the typical current conditions and visibility for diving the Heian Maru are not included in our current dataset. Divers planning to explore this historic wreck, sunk in 1944, should consult local dive operators in Chuuk (Truk) Lagoon for the most up-to-date conditions. The wreck itself is a substantial 155.8m x 20.1m vessel.