Your Guide to Chuuk Diving Sites

Betty Bomber

At a max depth of 18m/60 ft, lie the remains of a Japanese Mitsubishi G4M plane wreck, known as the Betty Bomber, that crashed into the lagoon in 1944. While not as deep or extensive as the shipwrecks, it offers a fascinating look at the remnants of an aircraft from WWII, with its radio, machine guns, and even a lavatory. The fuselage is still intact so divers can see the cockpit and wings clearly, with many small reef fish, anemones, and coral growth around the wreck.

Fujikawa Maru

This military cargo ship is the one of the most famous and photographed wreck dives in Truk, with the maximum depth of 37m/121 ft. The Fujikawa Maru carried planes and other military equipment of the Imperial Japanese Navy, and scuba divers can now explore its holds, where the remains of Mitsubishi Zero fighter planes, spare plane parts (belly tanks, propeller blades, tires and wheels), shell casings, machine guns, gas masks, cooking utensils, beer bottles, fuel drums, and much more are still stored. The ship’s superstructure sits upright and is adorned with colorful corals and anemones with abundant reef fish, including angelfish and butterflyfish, as well as reef sharks and turtles.

Heian Maru

At 150 meters (492 feet) long, the Japanese submarine tender, Heian Maru, is the largest wreck in Truk Lagoon. Its purpose was to carrying torpedoes, deck guns, and supplies for the Japanese subs during the Pacific War. Located at a depth of only 9-23 meters (30-115 feet), the wreck is shallow enough for easy access, and divers can explore the ship's enormous engine room and scattered torpedoes. Also periscopes, China ceramics, telephones, radio equipment, medical kits, and beer bottles are visible. The wreck attracts large schools of fish, coral growth, and offers a thriving habitat a which marine species like barracuda and jacks can hunt.

Hoki Maru

A large freighter carrying military supplies, the Hoki Maru offers a unique experience because of the heavy equipment, like bulldozers and trucks, still lying in its hold at 21-50 meters (69-165 feet). The wreck was torn apart in the attack, with massive sections still intact and others scattered across the seabed. Diver can explore this coral-encrusted wreck with fish schools, critters, and sea anemones. Every Chuuk dive here reveals something new.

I-169 Submarine

The Japanese sub I-169 is the only known submarine wreck in the lagoon. The forward section was blown apart by Japanese depth charges after the submarine was accidentally flooded. The conning tower is mostly complete but lies to the side of the submarine, and the aft section is relatively intact. This is one of the few wrecks in Truk where penetration is not recommended due to the frequent silt outs.

Nippo Maru

The Nippo Maru is an exciting 21-47m (69-154 ft) deep wreck with plenty to see, making it one of the all-time diver favorites in Truk. Scattered over the wreck is a small Japanese battle tank, the remains of trucks, and twin-barrelled anti-aircraft guns. Down in the holds are various types of munition, range finders, mess gear, beer bottles, and water tanks. The spectacular engine room is widely believed to be the first point of contact by enemy torpedoes during Operation Hailstone.⁠⁠ The bridge is probably the best intact example in Truk with the ship’s telegraph and steering binnacle still in remarkable condition. School of barracudas can be sighted here.

Rio de Janeiro Maru

The Rio de Janeiro Maru was a luxury passenger liner that was converted for military use during WWII. It is one of the larger wrecks in Truk Lagoon, offering divers the chance to explore spacious cargo holds that contain hundreds of beer bottles, some still in their cases, the bridge, and even the deck's anti-aircraft guns. At a depth of 9-35 meters (30-115 feet), the wreck is relatively shallow, making it easy to navigate and a good site for Chuuk scuba divers of all levels.

San Francisco Maru

A Japanese cargo ship, the San Francisco Maru is the one of the deepest wrecks in Truk Lagoon, at about to 50-64 meters (164-210 feet). It is known as the "Million Dollar Wreck" because of the incredible and valuable artifacts still on board. Divers can see tanks, trucks, mines, bombs, and ammunition in the ship's holds. This is a technical dive due to the depth, but it offers an incredible exploration of WWII history, together with some beautiful local marine life and occasional sightings of large pelagic species. To dive in Truk Lagoon at this level requires advanced training, but the reward is unmatched.

Shinkoku Maru

This large tanker sits in about 12-40 meters (40-130 feet) of water and is one of the most beautiful wrecks in the lagoon, being heavily encrusted with soft corals, sponges, and sea fans. The ship is remarkably intact, and divers can explore the bridge, crew areas, engine room, and infirmary, where medicine bottles and surgical equipment are still visible. Large schools of fish might accompany divers that linger to admire the vibrant coral formations.

Unkai Maru

This craft served as a Japanese cargo vessel (freighter) during the war. Built in 1905, it was initially a merchant ship used for transporting goods, including coal and raw materials, across Japanese trade routes. As the war escalated, the Unkai Maru was requisitioned by the Japanese Navy to support military operations, carrying supplies and ammunition to various outposts in the Pacific.

The wreck now lies at a depth of 18-44m (60-144 ft). It is considered to be the final resting place of Japanese soldiers and seamen since the forward holds contain many personal items including gas masks, shoes, china (with the 5-point blue star insignia of the Imperial Japanese Army), and numerous bottles. The engine room is small but accessible. The aft holds are largely empty, but in the stern are depth charges and an old-fashioned steering quadrant. The original gun maker’s markings on the Unkai’s bow gun are clearly visible, showing that it was manufactured in 1898.

Yamagiri Maru

Sitting at a depth of 15-33 meters (49-108) feet, the Yamagiri Maru is known for the visible damage it sustained during the Operation Hailstone attack, making it one of the more historically significant dives. Another transport ship, it contains massive 14-inch battleship shells in its hold. Divers can enter the engine room and view its large propellers. It is such an incredible spot for seeing spectacular coral formations, reef fish, and even occasional manta rays. When you dive Chuuk and visit this site, you see the raw power of the attack preserved underwater.