Cajón del Maipo is a canyon located in the Andean southeastern portion of the Santiago Metropolitan Region, Chile. It encompasses the upper Maipo River basin, where the river has entrenched itself in a narrow valley. The zone features a series of confluent rivers such as El Volcán River, Yeso River and Colorado River, as well as other minor streams, including San Gabriel, Manzanito, Coyanco, El Sauce, El Manzano and San José. The main locality is San José de Maipo, capital of the commune that includes all of the Andean sector of the Metropolitan Region. The towns located here from the pre-Andean area until well within the Andes mountains are: La Obra, Las Vertientes (the two latter conurbated with the city of Santiago de Chile), El Canelo, El Manzano, Guayacán, San José de Maipo, El Melocotón, San Alfonso, El Ingenio, San Gabriel y Melosas, Los Maitenes, Alfalfal, El Romeral, Queltehues, El Volcán, Baños Morales and Lo Valdés.