Bougainville: World War II Japanese Leftovers
Bougainville became Australian after WWI (it was German before that). In 1942, Japanese invaded and occupied the whole island, and went on fortifying it (many of the those fortification was still the most sturdy and long-lasting cement constructions in Bougainville to this day. Australia and USA began heavy bombardment of Bougainvile in 1943 (some of those bombs still lie unexploded deep in the jungle). The Japanese however held on to Bougainville until 1945. Some of the leftover tanks and guns and planes lies scattered around the island or collected in mini open air museums, like a place near Kieta.