Dive into the depths of Kaiyama Underground Bunker, a hidden stronghold built by the Yokosuka Naval Air Corps during World War II. Partially open to the public, this site also hosts rare tours. Let’s delve deeper into this historical legacy. Preserved history since 1944: Kaiyama Underground Bunker The Kaiyama Underground Bunker, located in Oppamacho, Yokosuka … Continue reading Kaiyama Underground Bunker | YOKOSUKA