Matsushiro Underground Tunnel (Zōzan)

photo by photo: Qurren ( talk ) Taken with Canon IXY 10S (Digital IXUS 210) · CC BY-SA 3.0

photo by photo: Qurren ( talk ) Taken with Canon IXY 10S (Digital IXUS 210) · CC BY-SA 3.0

Up to ten thousand workers a day dug 10 km of tunnels, and stopped at 75%.

You walk through the section open to the public, wearing the compulsory helmet handed out at the entrance, along a narrow tunnel cut into the rock beneath Zōzan hill.

A complex of tunnels dug in secret between November 1944 and August 1945, when the Imperial General Staff prepared a shelter there to move the headquarters and the imperial family in the event of an invasion of Japan: three networks of tunnels totalling about 10 kilometres. About 7,000 Korean forced labourers and 3,000 Japanese worked there, up to 10,000 people a day in April 1945; work stopped, 75% complete, with the announcement of the surrender on 15 August. Since 1990 about 500 metres of the Zōzan tunnel have been open to the public; today the complex also partly houses a seismic observatory.

ℹ️ Free admission, 9:00–16:00 (last entry 15:30), closed on the third Tuesday of the month and from 29 December to 3 January. Helmets provided and compulsory; sandals or heels are not advisable because of the uneven ground.

🚉 Old station · 17 min walk

Sources: ja.wikipedia.org · city.nagano.nagano.jp

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