The project is highlighting locations across the 9-square-kilometer island that are frequently overlooked by visitors to Chuuk, which is best known for its underwater attractions.<\/p>\n
The lagoon\u2014around 5,250 kilometers southwest of Hawaii\u2014was the site of the Imperial Japanese Navy\u2019s main base in the central Pacific during World War II, but was the target of a two-day attack by US carrier-based aircraft in February 1944 known as Operation Hailstone.<\/p>\n
Over the course of the raid, more than 50 Japanese ships\u2014including warships, cargo vessels and even a submarine\u2014were sunk. Scuba diving of the remarkably well-preserved wrecks began after the famed underwater explorer Jacques Cousteau filmed a documentary about the fabled \u201cghost fleet\u201d in 1969 and, more than half-a-century later, the wrecks are still the reason most people visit.<\/p>\n Mapping the History On Shore<\/p>\n By charting the history that is above the waves, Ishii hopes to share more about the Japanese community that lived on what is today Tonoas, but was referred to as Dublon during the Spanish occupation of the islands in the late nineteenth century before becoming Natsushima\u2014or \u201cSummer Island\u201d\u2014when the Japanese took control of the archipelago from Germany in October 1914.<\/p>\n \u201cI am fascinated by an area and a period that are less well-known in Japan, despite the fact that prewar Japanese were heavily invested in these islands,\u201d says Ishii, a researcher at the Center for Southeast Asian Studies at Kyoto University.<\/p>\n Ishii first visited Chuuk in December 2019 to take part in a maritime archaeology field expedition and met Bill Jeffery, of the University of Guam, with whom he has since collaborated on surveys of historic Japanese sites, both on the seabed and on Tonoas.<\/p>\n \u201cThe remnants of the years of the Japanese occupation have survived better on Tonoas than elsewhere in Chuuk state primarily because the capital functions of the state were moved to Weno island after Japan\u2019s surrender,\u201d Ishii tells Nippon.com. \u201cAnd even now, we still do not know how many sites related to Japan\u2019s decades of control of Chuuk remain on other islands in the lagoon.\u201d<\/p>\n Today, the only way to reach Tonoas is by boat, with the crossing from Weno taking about 20 minutes. The island is largely covered in thick jungle and fringed with mangrove swamps, rising to two high hills at the western end, Tonomwan and Tonofefan.<\/p>\n The main sites of historic interest can be accessed via the unpaved tracks that crisscross the island. Dublon Town was clustered around a small inlet on the south side of the island and was a bustling community of around 800 Japanese inhabitants during the prewar years, with an outdoor movie theater, the offices of the Japanese-language newspaper, caf\u00e9s, and much of the infrastructure that could be found in a small town in Japan.<\/p>\n The area was targeted during the US attacks and most of the buildings were destroyed, with little remaining today. Farther along the coast to the west is the seaplane base, which was again heavily bombed, with the shell of the power plant building and a large underground bunker designed to store aircraft slightly inland.<\/p>\n Hospitals, Schools, and More<\/p>\n Surrounded by thick undergrowth in the hills above Dublon Town is the shell of a hospital built in 1928, the only one in Chuuk that was open to local people. After war broke out, the Japanese occupying forces used it to treat wounded or ill service personnel.<\/p>\n The main buildings are of concrete and have survived remarkably well. Wards are laid out neatly and there is a spacious grassed area in the center. Knee-high pillars and steps along one side indicate where elevated wooden wards once stood. The floor of one room\u2014possibly used for operations\u2014remains tiled, and the original garden still contains native Japanese plants.<\/p>\n A few hundred meters away is a school built by the Japanese for Chuukese children, although it later served as the local headquarters for the Japanese Territorial Government for the South Seas. Nearby is a stone memorial to businessman and adventurer Mori Koben\u2014still a common family name among Chuukese\u2014who arrived in the islands in 1891 and built a trading empire.<\/p>\n The island\u2019s current elementary school stands on the site of the Japanese military communications center, with stone pillars still upright at the entrance and the concrete bases of radio antennas dotted amid the undergrowth. A reinforced air raid bunker is also within the grounds of the school, with the Japanese moving their communications equipment to a larger tunnel burrowed into a nearby hillside after the 1944 air raids.<\/p>\n The site is historically significant as it was from here in April 1943 that a message was sent providing the details of Admiral Yamamoto Isoroku\u2019s inspection tour of military facilities throughout the South Pacific. Unbeknown to the Japanese, the US had cracked the military code. On April 18, 16 P-38 lightning fighters intercepted Yamamoto\u2019s aircraft and its escort of six Zero fighters over the Solomon Islands. Yamamoto, widely regarded as one of imperial Japan\u2019s most capable military leaders, was killed.<\/p>\n![\"An](\"https:\/\/www.europesays.com\/japan\/wp-content\/uploads\/2026\/06\/3019023.jpg\")
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An Aichi E13A float plane sunk during World War II is among the attractions for divers who flock to Chuuk\u2019s waters. (\u00a9\u00a0Julian Ryall)<\/p>\n![\"The](\"https:\/\/www.europesays.com\/japan\/wp-content\/uploads\/2026\/06\/3019024.jpg\")
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The courtyard of the Tonoas hospital. (\u00a9\u00a0Julian Ryall)<\/p>\n
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