The Iron Triangle Battlefield is the area that connects Gimhwa, Pyeonggang and Cheorwon. This area had the highest number of casualties during the Korean War with the Baekmagoji Battle and Oseongsan Battle. The Iron Triangle Battlefield was prohibited to the public after 1953 when the war ended in a ceasefire. Yet the reality of the war only began surfacing from November 1989.The Iron Triangle Battlefield was the headquarters and frontline of the North Korean Army. This area had the unique natural advantage of being a difficult target for Allied forces to attack, but remained an easy area for North Koreans to defend. At the old battlefields are the labor headquarters, the 2nd tunnel and the remains of a train with a sign that reads 'The iron horse wants to run'. The Labor Headquarters, a Russian-style 3-story building, was built by compulsory fund raising and labor mobilization. Many people who were here during the anticommunist movement were later tortured and killed. Behind the building remains of people, bullets and iron chains can still be found even to this day.This is also the area where the 2nd tunnel, 108km north from Seoul, was made by North Koreans who were planning to invade South Korea. It is also known as the gathering area of seasonal birds and is a popular bird-watching spot.