During
the Qing dynasty, the area that is modern-day Hengchun was governed as part of Fengshan County. However, being a distant and sparsely populated region, the Qing found it hard to govern the area. Things took a turn following the
Rover incident and the
Mudan incident, causing the Qing government to decide to maintain a stronger presence in the area.
Shen Baozhen, originally dispatched to Hengchun after the Mudan incident, suggested that a fort be built in the area and named it "Hengchun", meaning "constantly spring", referring to the region's fair weather. Construction ran between 1875 and 1879 and was designed by Liu Ao, who would later design the
Walls of Taipei. Since its founding, the fort was damaged multiple times. A
typhoon in 1908 caused severe damage to the wooden gatehouses, and large parts of the walls were further damaged during World War Two and the
1959 Hengchun earthquake. Additionally, parts of the wall were removed to construct roads, leaving only portions of the wall near the north and east gates still standing. The castle was first protected as a national historical site in 1979, and the
Tourism Bureau began repairs to the south and east gates in 1979 and 1986, respectively, including building replica gatehouses above both gates. However,
termites in the east gatehouse caused it to collapse again. == Structure ==