Matsushiro Imperial Underground Headquarters

The Matsushiro Imperial Underground Headquarters are the remains of a vast, secret military complex begun in November 1944 beneath three mountains at Matsushiro, now part of Nagano City. As defeat approached, the Imperial Army planned to move Imperial General Headquarters, government ministries and the Emperor here for a final battle on the mainland. About ten kilometres of tunnels were dug in roughly nine months. The workforce included many Korean labourers, a large number brought under forced or coerced mobilisation, working alongside Japanese labourers in dangerous conditions. Japan surrendered in August 1945 before the complex was used.

Around 500 metres of the tunnels beneath Mount Zōzan are now open, left deliberately rough, with rock-drill marks and rail traces still visible. The cold, dim passages carry an oppressive atmosphere, and some visitors describe the place as unsettling or speak of the ghosts of its history. Such reactions are understandable, subjective responses to a site of real hardship and loss, and should be held with care rather than treated as sensational.

Opened to the public around 1989, the site has been preserved largely through the efforts of local citizens determined to convey its full history, including the forced labour that built it; a nearby memorial centre records these testimonies. Matsushiro stands as an important place of remembrance and peace education, valued because it confronts an uncomfortable chapter of the war honestly.

A roughly 500-metre section of the Zōzan tunnels is open to the public, generally from 9:00 to 16:00 (last entry 15:30), free of charge, and closed on the third Tuesday of the month and over the New Year period; visitors are issued a helmet before entering. The tunnels are unlit in places and left in their original rough state, so sturdy footwear and care are advised.

The site is reached by bus from Nagano Station to Matsushiro, with parking nearby, and an adjacent memorial facility interprets its history. As a place connected to forced labour and wartime suffering, it is best approached quietly and respectfully; checking current opening days locally is recommended, as the site can close for maintenance.