Apurimac, a river of Peru, which rises in lat. 15° 21' E., lon. 72° 10' W., not far from the sources of the river Camana, in a lake situated between spurs of the mountains of Cay-lloma. It flows N. for a short distance, then N. N. W. for about 105 m., receiving several other streams, to its junction with the Man-taro in lat. 12° S., and from that point is known as the Tambo as well as the Apurimac. Hence it flows first N. E., then N. N. W. for more than four degrees of latitude nearly parallel with the Urubamba, and they unite and form the Ucayale in lat, 8° 30' S., lon. 73° 24' W. The Apurimac and the Urubamba collect the moisture of the high plateau of the interior of Peru, and are among the largest tributaries of the Amazon, the former being sometimes reckoned its source.