Taiheiyo Belt

The Taiheiyō Belt (太平洋ベルト, Taiheiyō beruto^?, literally "Pacific Belt"), also known as the Tokaido corridor, is the name for the megalopolis in Japan extending from Ibaraki Prefecture in the north to Fukuoka Prefecture in the south, running for almost 1,200 km (750 mi).

The urbanization zone runs mainly along the Pacific coast (hence the name) of Japan from Kantō region to Osaka, and the Inland Sea (on both sides) to Fukuoka, and is concentrated along the Tōkaidō-Sanyō rail corridor. A view of Japan at night clearly shows a rather dense and continuous strip of light (demarcating urban zones) that delineates the region.

The high population is particularly due to the large plains – the Kantō Plain, Kinai Plain, and Nōbi Plain – which facilitate building in mountainous Japan. Coastal regions are at high risk of earthquakes and tsunamis, due to the nearby Nankai Trough (Nankai megathrust earthquakes) and Sagami Trough, notably the 1923 Great Kantō earthquake, and further damaging earthquakes are expected in the region; the combination of population density and seismic activity is responsible for the high-impact earthquake and tsunami risk in Japan.

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