Early morning on Quay Son river

Khoi Tran Duc - Hanoi, Viet Nam

The Quây Sơn River (Vietnamese: Sông Quây Sơn) or Guichun River (Chinese: 归春河) is a river of Cao Bằng Province, Vietnam and of Guangxi province, China. The river originates in China at Jingxi County (靖西县) in the Chongshan Mountain Range (Chóngshān jùnlǐng 崇山峻岭). For part of its length it runs along the Chinese–Vietnamese border, including the scenic Ban Gioc–Detian Falls.