This Japanese fortress is located in Kokas city center, Kokas district, Fak-Fak, West Papua. This fortress is one of the Japanese fortresses during World War II. It was build by making a cave under a hill by a beach side. In this fortress, there are three gates and a bunker connected by the 138 meter long cave.
Source: indonesia.travel
http://assets.kompas.com/data/photo/...055620X310.jpg
