The Toisan mountain range runs East/West off the western side of the Andes mountains. Running North/South from this Toisan range lies the Cordillera de La Plata of which Los Cedros is the Southern most area. The reserve lies on the ascending slopes of the La Plata range consisting of steep river valleys and high ridges. Los Cedros has altitudes ranging from 1000 meters at the entrance, up to Cerro de La Plata at 2700 meters. This is the last ridge in the Cordillera de La Plata. The reserve encompasses four main watersheds; the Rio Manduriyacu, the Rio Verde, the Rio Los Cedros, and the south bank of the Rio Magdalena Chico. Keeping these rivers protected and clean for those that live downriver is a main objective for Los Cedros Reserve.