The Río Grande
(or Río Guapay) in Bolivia rises on the southern slope of the Sierra de Cochabamba
, east of the city of Cochabamba
, at . At its source it is known as the Río Rocha
and crosses the Cochabamba valley basin in a westerly direction. After 65 km the river turns southeast
and after another 50 km joins the Río Arque
at and an elevation of 2.350 m.
From this junction the river is given the name Río Caine for 162 km and continues to flow in a southeasterly direction, before it is called Río Grande. After a total of 500 km the river turns northeast and in a wide curve flows round the lowland city of Santa Cruz.
After 1.438 km, the Río Grande joins the Río Ichilo at which is a tributary to the Río Mamoré.