History: My great grandpa was a soldier in WWII fighting against the Japanese. He was stationed at a base in the Phillipines when the Japanese attacked it. The soldiers were told to surrender. If a soldier surrendered, he was taken prisoner by the Japanese. My great grandfather and other soldiers decided to go against orders and escape into the jungle in order to avoid the being captured. They might have built forts like this one for shelter with any materials they could find. He survived by attacking Japanese soldiers with the little ammo he had, and then taking all of their equipment such as ammunition, belts, clothing, guns, knives, etc... He was reported as Missing In Action, but after five years of struggling in the jungle American forces won the war, taking back the Phillipines.