Pothong River

The Pothong River (Pot'ong River, Potonggang) is a river in North Korea. It flows through the capital Pyongyang and is a tributary of the Taedong River. 
There are several bridges across the river in Pyongyang, including one at its mouth called the "Pothong Bridge"; however, the largest is the one known as "Ansan Bridge", , which supports the main east-west divided highway.
Prior to 1946, the arable land west of Pyongyang alongside the river (the flood plain), down to where it entered the Taedong River was subject to annual flooding. This area was known as "Tosongrang". The farmers there annually rebuilt their homes after the floods subsided, so the construction was, perforce, of a temporary nature, huts and even pit-houses. In 1946 the river was channelized through "Tosongrang" as the "Pothong River Improvement Project". "Tosongrang" is now part of Pyongyang.
In 1971, in a park on Mount Bonghwa, a hill on the left (east) bank of the river, the government erected a monument for the "Pothong River Improvement Project", . It commemorates Kim Il-sung's 1945 visit to "Tosongrang" and the 1946 channelization.
In 1976 the North Korean postal service (DPRK) issued a stamp commemorating Kim Il-sung's 1945 visit to "Tosongrang". In 1998, they issued a stamp souvenir sheet showing Kim Il-sung breaking ground for the construction of the channelization project.