The Bukhansan National Park in Seoul and Gyeonggi covers an area of 79.92 km2 (30.86 sq mi) and was established on 2 April 1983. Bukhansan means "mountains north of the Han River." The park contains forested areas, temples and granite peaks. The three main peaks are Baekundae, 836.5 m (2,744 ft), Insubong, 810.5 m (2,659 ft) and Mangnyeongdae, 799.5 m (2,623 ft). Due to its popularity with hikers and Seoul residents, some trails are closed on a rotation basis to protect the local environment.
The Bukhansanseong Fortress is located in the park, together with its 9.5 km (5.9 mi) long defensive wall. A fortress was first built on this site in 132 AD to protect Seoul from foreign invasions, and it was expanded to its current size in 1711. It was reconstructed after damage sustained in the Korean War. Despite its name, this mountain is in Seoul, South Korea, so this mountain should not be confused with North Korea.