In waters devoid of normal ocean currents, divers can easily swim across decks littered with gas masks and depth charges and below deck can be found evidence of human remains. In the massive ships’ holds are the remnants of fighter aircraft, tanks, bulldozers, railroad cars, motorcycles, torpedoes, mines, bombs, boxes of munitions, radios, plus thousands of other weapons, spare parts, and other artefacts. Of special interest is the wreck of the submarine I-169 Shinohara which was lost when diving to avoid the bombing. The submarine had participated in the attack on Pearl Harbour in December 1941.

 

During World War II, Truk Lagoon was the Empire of Japan’s main base in the South Pacific theatre. Truk was a heavily fortified base for Japanese operations against Allied forces in New Guinea and the Solomon Islands, serving as the forward anchorage for the Japanese Imperial Fleet.

 

Truk Lagoon was considered the most formidable of all Japanese strongholds in the Pacific. On the various islands, the Japanese Civil Engineering Department and Naval Construction Department had built roads, trenches, bunkers and caves. Five airstrips, seaplane bases, a torpedo boat station, submarine repair shops, a communications centre and a radar station were constructed during the war. Protecting these various facilities were coastal defence guns and mortar emplacements. Due to its heavy fortifications, both natural and manmade, the base at Truk was known to Allied forces as “the Gibraltar of the Pacific.”

 

A significant portion of the Japanese fleet was based at Truk, with its administrative centre on Tonoas (south of Weno). At anchor in the lagoon, were the Imperial Japanese Navy’s battleships, aircraft carriers, cruisers, destroyers, tankers, cargo ships, tugboats, gunboats, minesweepers, landing craft, and submarines. Some have described Truk as Japan’s equivalent of the Americans’ Pearl Harbour.

 

In 1944, Truk’s capacity as a naval base was destroyed through naval air attack. Forewarned by intelligence a week before the US raid, the Japanese had withdrawn their larger warships (heavy cruisers and larger vessels) to Palau. Once the American forces captured the Marshall Islands, they used them as a base from which to launch an early morning attack on February 17, 1944 against Truk Lagoon. Operation Hailstone lasted for three days, as American carrier-based planes sank twelve smaller Japanese warships (light cruisers, destroyers, and auxiliaries) and thirty-two merchant ships, while destroying 275 aircraft, mainly on the ground. The consequences of the attack made “Truk Lagoon the biggest graveyard of ships in the world”.

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The attacks for the most part ended Truk as a major threat to Allied operations in the central Pacific. The Japanese garrison on Eniwetok was denied any realistic hope of reinforcement and support during the invasion that began on February 18, 1944, greatly assisting U.S. forces in their conquest of that island. Truk was isolated by Allied (primarily U.S.) forces, as they continued their advance towards Japan, by invading other Pacific islands, such as Guam, Saipan, Palau, and Iwo Jima. It was attacked again from 12 to 16 June 1945 by part of the British Pacific Fleet during Operation Inmate. Cut off, the Japanese forces on Truk and other central Pacific islands ran low on food and faced starvation before Japan surrendered in August 1945.