Changja River

The Changja River (Korean: 장자강) is a river in North Korea. The river originates near Sobaeksan Mountain in the Nanglim Mountains east of Ganggye-gun, North Pyongan Province and flows northwest into the Yalu River.

Changja River
Location
Location	North Pyongan Province
Physical characteristics
Source
• location	Sobaek Mountains
Mouth
• location	Yalu River
• coordinates	40°57′56″N 126°03′47″E
Length	239 km
Basin features
Progression	Yalu → Yellow Sea
River system	Yalu

Until 1976, the river was called Tongno-gang. It is 239 km long, has a catchment area of 207 km².

The area was the scene of fierce fighting during both the guerrilla war against the Japanese occupation and also during the Korean War. These events were later processed in numerous books and films, for example “On the Banks of Tongro-gang” (독로강 기슭에서 Tongro-gang kisŭlgesŏ) by Kim Hak-yŏn from the Year 1951.

During the first five-year plan (1957–1961), a hydroelectric power station with a capacity of 90 megawatts was built on Tongro-gang. Construction had already begun in 1937, but the systems were dismantled again in 1943.

In the northern interior of the country there is hardly any land that can be used for agriculture. The Tongro-gang valley is the region's most important growing area. Mainly corn is harvested here.