City (pop., 2007 est.: 2,139,535), western Colombia. Lying on both sides of the Cali River, it was founded in 1536. Located far from the coast, it did not develop economically until the 20th century, when the upper Cauca River was harnessed to generate electrical power and prevent flooding. It is a major service centre for area products and rivals Bogotá, Barranquilla, and Medellín as an industrial centre. Beginning in the late 20th century, Cali became notorious for its trade in illegal narcotics.