Located in Khao Sam Lan National Park, south of WatPhraPhutthachai, this historic attraction displays the remnants of the Japanese occupation of the area. During World War II, Japanese soldiers used KhaoDaengarea as a military base as well as prison for wartime captives. There remain traces of holes caused by the bombs left behind by the Japanese soldiers. The buildings left behind by the Japanese soldiers include a commanding tunnel, trenches along the valley, a commanding room, a treasure room, and bunker lines.
The park is located on the Bangkok-Saraburi Road, on Highway No. 1, Phahonyothin Road, approximately 16 kilometers south of Saraburi. Departing from Bangkok, turn right to make a U-turn before reaching Km. 102, continuing onto Highway No. 3042 and then 3046. Continue on the asphalt road for 8 kilometers.