The world's greatest shipwreck graveyard — 60 Japanese ships under one lagoon
Chuuk (formerly Truk Lagoon) is the most celebrated wreck diving destination on Earth — a Pacific atoll where the US Operation Hailstone in February 1944 sank over 60 Japanese ships in two days, creating an accidental museum of wartime vessels now colonised by sea fans, lionfish, and coral. Intact cargo holds still contain Zero fighters, tanks, sake bottles, and human remains. Weno is the main island and point of arrival.
Truk Lagoon was Japan's main Pacific naval base — 'the Gibraltar of the Pacific' — home to the Combined Fleet's headquarters and over 400 aircraft. On 17–18 February 1944 the US Navy launched Operation Hailstone, attacking with 9 carriers and 150 support ships; in 48 hours they sank 50+ ships, destroyed 270 aircraft, and killed ~4,000 Japanese service members. The atoll's name was changed from Truk to Chuuk in 1990 to distance it from its wartime associations; its wrecks were declared a Historic Preserve in 2011.