Naval Arsenal Ordnance Department Underground: War ruins in a maze-like subterranean space

The article reports that previously veiled underground shelters, used as air-raid shelters within Self-Defense Forces bases, are being revealed one after another. It mentions the former Navy Takeyama Marine Corps underground shelter remaining at Yokosuka Education Unit (Miyukihama) and the former Navy Tsuu… remaining at Kurihama Garrison (Kubiri), describing maze-like subterranean spaces and war ruins within the bases.