This cave is located in the village Ngreco, and Poyahan, Seloharjo Village, District Pundong. Japan's cave is a relic of World War II. As a means of military defense in the era of Japan in 1942-1945, especially after Japan's allies defend themselves from the arrival in Indonesia.
Japanese caves are built to meet the needs of a guerrilla war since Japan estimates that the allies would come through the southern ocean and landed on the coast Parangtritis. In this cave found 18 bunkers building remains largely intact. Diverse forms of the bunker, and also have different functions, such as a lookout, firing chamber, meeting room, storeroom and kitchen. Average wall thickness of 50-70 cm, of reinforced concrete, cement and stone padas are already available in the vicinity. Bunkers were built close together (30 m), and connected by a trench outside the tall (1 m).