Ban Gioc–Detian Falls
Coordinates: 22°51′23″N 106°43′19″E / 22.8564°N 106.7220°E / 22.8564; 106.7220
Ban Gioc – Detian Falls (Vietnamese: thác Bản Giốc, Chinese: Détiān pùbù, Bǎnyuē pùbù 板約瀑布, 德天瀑布) is a collective name for two waterfalls on the Quây Sơn River (Chinese: Guichun River, 归春河), that straddle the international border between China and Vietnam; more specifically located between the Karst hills of Daxin County, Guangxi, and Trùng Khánh District, Cao Bằng Province. The waterfall is 272 km (169 mi) north of Hanoi.
Characteristics
Over thousands of years the waterfall has eroded its crest and slowly moved upstream. It currently appears to be two waterfalls most of the time but when the river is swollen due to summer rains can form one fall again.
In Vietnamese, the two falls are considered as two parts of one waterfall with the sole name Bản Giốc. The two parts are thác chính (Main waterfall) and thác phụ (Subordinate waterfall). Chinese texts sometimes name both falls from the Détiān falls on the Chinese side.