The is a twin-bore motorway

tunnel A tunnel is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two portals common at each end, though there may be access and ve ...

on the Chūō Expressway located on the border of the cities of Kōshū and Ōtsuki in

Yamanashi Prefecture is a prefecture of Japan located in the Chūbu region of Honshu. Yamanashi Prefecture has a population of 787,592 (1 February 2025) and has a geographic area of 4,465 km2 (1,724 sq mi). Yamanashi Prefecture borders Saitama Prefecture to the n ...

, Japan. It is located about west of the capital

Tokyo Tokyo, officially the Tokyo Metropolis, is the capital of Japan, capital and List of cities in Japan, most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is List of largest cities, one of the most ...

. It was built in 1977.Martin Fackler (2 December 2012)
Nine Killed When Highway Tunnel Collapses in Japan
''

New York Times ''The New York Times'' (''NYT'') is an American daily newspaper based in New York City. ''The New York Times'' covers domestic, national, and international news, and publishes opinion pieces, investigative reports, and reviews. As one of ...

Ceiling collapse

At approximately 8 am on December 2, 2012, nearly 150 concrete ceiling panels inside the Tokyo-bound Sasago Tunnel collapsed, crushing three vehicles, including a van, carrying six persons, that caught fire. The fallen panels were thick and weighed each. The caved-in point was from the Tokyo-side exit and spanned a length of . Smoke could be seen billowing from the Kōshū entrance to the tunnel. Nine people died and two were injured, making it the deadliest roadway accident in Japanese history. The tunnel was closed for a period of 27 days for repairs and removal of ceiling panels, before the south tube reopened on December 29. The north tube, where the collapse happened, reopened on February 8, 2013. The nature of the collapse closely resembled a similar ceiling collapse in the Fort Point Channel Tunnel in

Boston, Massachusetts Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeas ...

in 2006. File:SasagoTNnaibu.JPG, Inside of the tunnel before the accident. Ceiling panels are visible on the top File:Sasago tunnel ceiling panel is removed, the ventilation system were built.JPG, Temporary opening of tunnel with ceiling panels removed and replaced by ceiling fan File:Sasago Tunnel(Chūō Expwy) 3D model 2.png, Cross section model of Sasago Tunnel File:Sasago Tunnel(Chūō Expwy) collapsed 3D model 2.png, Model showing collapsed ceiling panels

References

External links

* {{Authority control Transport buildings and structures in Yamanashi Prefecture Roads in Yamanashi Prefecture Road tunnels in Japan Tunnel disasters 2012 industrial disasters December 2012 in Japan Tunnels completed in 1977 Road incidents in Japan 2012 road incidents in Asia Kōshū, Yamanashi Ōtsuki, Yamanashi Building and structure collapses in 2012 Building and structure collapses in Asia