The Río Grande (or Río Guapay) in Bolivia rises on the southern slope of the Cochabamba mountains, east of the city Cochabamba, at -17.43639°N, -65.87278°W. At its source, it is known as the Rocha River. It crosses the Cochabamba valley basin in a westerly direction, turning south east after 65 km and after another 50 km joining the Arque River at -17.70278°N, -66.24583°W and an elevation of 2,350 m. From this junction the river receives the name Caine River for 162 km and continues to flow in a south easterly direction, before it is called Río Grande. After a total of 500 km the river turns north east and in a wide curve flows round the lowland city of Santa Cruz. After 1438 km, the Río Grande joins the Ichilo River at -15.8025°N, -64.72972°W which is a tributary to the Mamoré.