The catchment area of the Platte River with the South and North Platte Rivers
The South Platte River (also South Platte ) is next to the North Platte River one of the headwaters of the Platte River in the USA .
The 711 km long river has its source southwest of the city of Fairplay , Colorado , in the Rocky Mountains . In its course - mainly in easterly directions, the river flows through Colorado and its capital Denver in particular, as well as the US state of Nebraska in the lower reaches . In North Platte , the South Platte River and North Platte River merge to form the Platte River. The city of Denver was founded at the confluence of the South Platte and Cherry Creek.