Story of Sergeant Shoichi Yokoi is fascinating. When the Americans retook Guam in 1944, many Japanese soldiers refuse to surrender, so they hide in the jungle. Some longer than other. Yokoi managed to hide in the jungle for 28 years, but some local hunters discovered him in 1972. It turned out he knew the war was over in 1952, but explained "We Japanese soldiers were told to prefer death to the disgrace of getting captured alive". The real cave doesn't exists anymore, but there is a replica close to the original location in Talofofo Falls Resort Park. There isn't much explanation in English, but if you know the story, the cave is interesting.