Urubamba River

	Urubamba River (Río Urubambe)
	River
Country	Peru
Mouth	Ucayali River
Length	724 km (450 mi)

The Urubamba River (Río Urubamba) is a river in Peru. A partially navigable headwater of the Amazon River, it rises in the Andes to the south-east of Cuzco near the Puno Region border, where it is called the Vilcanota River (Rio Vilcanota). In the Sacred Valley, between Písac and Ollantaytambo, it is also called the Wilcamayu (sacred river). It flows north-north-west for 724 kilometers before coalescing with the lower Apurímac River to form the Ucayali River.

The Urubamba is divided into Upper Urubamba and Lower Urubamba, the dividing feature being the Pongo de Mainique, an infamous whitewater canyon.

John Walter Gregory, the British geologist, drowned in the river on June 2, 1932 while on a geological expedition to the Andes.

[edit] Upper Urubamba

The Upper Urubamba (Alto Urubamba) valley features a high population and extensive irrigation works. A number of ruins of the Inca Empire lie in the valley, including the Incan city of Machu Picchu.

[edit] Lower Urubamba

The Lower Urubamba (Bajo Urubamba) is relatively undeveloped and features a significant indigenous population consisting of the Campa tribes, principally the Machiguenga (Matsigenka) and Ashaninka. The economy is based on forestry and the nearby Camisea Gas Project. The main settlement in the region is the town of Sepahua. The lower Urubamba River was mapped for the first time in 1934 by Edward Kellog Strong III. He and two friends from Palo Alto, California, Art Post and Gain Allan John, navigated the river with its ferocious rapids by canoe and balsa rafts provided by the indigenous people along the banks. The mapping was done at the request of the Peruvian military when they heard of the expedition planned by the three 18 year olds. It was turned over to the military when the boys arrived in Iquitos. It was the only map of the river until it was mapped by satellite many years later. The names and places on the latest map came from the original map drawn by Edward Strong.