Located at Kangu at the base of Kangu Hill on the southern coast of Bougainville. The Japanese called the location "Buin" and "Mount Buin".
Built by the Japanese Navy as a bunker to store a generator. This bunker was used to relay power to a wireless station at Buin. After the Japanese surrender during late September 1945, occupied by the Australian Army, 2 Corps, headquarters.
Postwar, the bunker was used as a jail by the Australian administration. The outer door
is missing. Above the doorway is an Imperial Japanese Navy anchor. The interior of the bunker has high ceilings and is in excellent condition. Inside is the remains of of machinery inside.