Dive Site: Yamagiri Maru

About Yamagiri Maru

The Yamagiri Maru, a substantial Japanese cargo ship, offers an extraordinary dive into history within Truk Lagoon, Micronesia. As part of the famed "Ghost Fleet" resulting from Operation Hailstone in 1944, this wreck provides a unique blend of WWII relics and a thriving artificial reef. Its accessible depths make it suitable for a range of divers, from those exploring its exterior to experienced individuals keen on careful penetration. The wreck rests largely intact, presenting a fascinating structure for exploration. Corals have extensively colonized the ship's superstructure, transforming it into a vibrant habitat for diverse marine species. Artifacts such as shells and other wartime cargo are still evident, allowing a poignant glimpse into its past. Water conditions in Truk Lagoon are consistently warm, and currents around the Yamagiri Maru are generally mild, contributing to a comfortable and engaging dive experience. Visibility typically ranges from good to excellent, especially during the dry season, enhancing the appreciation of both the wreck's scale and its abundant marine inhabitants. Liveaboards are the preferred method for diving the Yamagiri Maru and other Truk Lagoon sites, enabling multiple dives over several days and efficient access to various wrecks. The combination of historical significance, marine biodiversity, and favorable diving conditions makes the Yamagiri Maru a compelling destination for wreck enthusiasts and underwater photographers alike.

Dive site facts: Yamagiri Maru

Depth

15–34 m

Typical dive

18–30 m, 50–60 min

Current

Mild

Visibility

15–40 m

Water temperature

28–30°C

Entry

Tender / stern lift

Level

Advanced Open Water Diver

Dive type

Wreck, historical, reef

Night dive

Possible

Region / port

Chuuk Lagoon, Micronesia

Coordinates

7.362, 151.838

Conditions & Currents

Currents around the Yamagiri Maru within Truk Lagoon are generally mild, making for relatively calm diving conditions. This low current environment is ideal for wreck exploration, allowing divers to leisurely navigate the ship's exterior and interior. Entry and exit are typically straightforward, often assisted by liveaboard tenders. Visibility can range from 15 to 40 meters, with the best clarity experienced during the dry season. While thermoclines are uncommon in the consistently warm waters, occasional rainfall can slightly reduce visibility. The calm conditions are generally forgiving for divers, though prudent gas planning is always essential, particularly for longer wreck penetrations.

Marine life & sighting chances

Batfish

common

Barracuda

common

Dogtooth Tuna

occasional

Reef Fish

common

Soft Corals

common

Anemones

common

Hawksbill Turtle

occasional

Whitetip Reef Shark

occasional

Nudibranchs

common

Crustaceans

common

Dive profile & how the dive runs

Diving the Yamagiri Maru typically begins with a descent along the mooring line to the ship's deck, which lies at around 15 to 18 meters. You can explore the forward cargo holds, where shells are often visible. Progressing along the wreck, divers can observe the extensive coral growth on the superstructure and the bridge area. Deeper sections, including the engine room and stern, reach approximately 34 meters, offering more advanced penetration opportunities. The turn point is often dictated by air consumption or bottom time, ensuring a safe ascent. Safety stops are usually conducted on the mooring line or along the ship's masts, which ascend towards shallower water, providing additional opportunities for observation of marine life.

Underwater photography

The Yamagiri Maru presents abundant opportunities for wreck and wide-angle photography. A wide-angle lens is ideal for capturing the immense scale of the ship and its cargo holds, as well as the dense coral growth. For interior shots and artifacts, dual strobes are essential to illuminate the often low-light environment and bring out colors, particularly for smaller details like sake bottles or machine parts. Maintaining excellent buoyancy control is crucial to avoid disturbing silt and to navigate confined spaces safely. When photographing marine life on the wreck, approach subjects slowly and avoid direct contact to preserve the delicate ecosystem. Patience often yields the best results for both historical artifacts and resident fish.

Combine with nearby dive sites

• Fujikawa Maru

  Known for its intact aircraft and cargo holds.

• San Francisco Maru

  A deeper, challenging wreck known as the 'Million Dollar Wreck' with tanks and trucks.

• Shinkoku Maru

  One of the most beautiful wrecks, heavily encrusted with soft corals.

• Nippo Maru

  Features an artillery gun, tanks, and other military equipment.

• Heian Maru

  A large submarine tender with torpedoes and periscopes.

• Gosei Maru

  A cargo ship with a variety of artifacts, including a bulldozer.

Getting there & logistics

Access to Truk Lagoon, including the Yamagiri Maru, is primarily via Chuuk International Airport (TKK). International flights typically connect through Guam, Palau, or other Micronesian hubs. Liveaboards are the most practical and popular way to experience the numerous wrecks in the lagoon, offering multi-day itineraries that maximize dive time and cover diverse sites. Transfers from the airport to liveaboard docks are usually arranged by the operators. Trip lengths typically range from 7 to 10 days. While there are no specific park fees for individual wrecks, some liveaboard packages may include general diving permits. Combining Truk Lagoon with other Micronesian destinations like Palau is common for extended dive trips.

Safety & environment

Diving the Yamagiri Maru, like other wrecks in Truk Lagoon, requires careful attention to safety protocols. The nearest recompression chamber is located in Chuuk itself, though emergency medical facilities are limited. Evacuation for serious medical incidents would likely involve transport to Guam or further, underscoring the critical need for comprehensive dive insurance that covers emergency medical treatment and evacuation. Divers should be proficient in buoyancy control and aware of entanglement hazards from lines and corroded structures. Wreck penetration should only be attempted by appropriately trained and experienced divers with proper equipment. Always dive with a guide familiar with the wreck, and adhere strictly to dive plans and depth limits.

Who it suits — and who it doesn't

FAQ

Yamagiri Maru FAQ

Liveaboards diving Yamagiri Maru

These liveaboards may visit Yamagiri Maru on selected itineraries — the exact dive sites depend on departure, weather and conditions.

Palau Siren

Micronesia

16 guests

$501/day

Solitude Gaia

Micronesia

18 guests40 m

$310/day

Palau Aggressor II

Micronesia

18 guests32 m

$292/day

Black Pearl

Micronesia

24 guests

$390/day

Ocean Hunter 3

Micronesia

16 guests29 m

$350/day

Pacific Master

Solomon Islands

20 guests30 m

$268/day