This reserve covers an area of 13,185 hectares, at an altitude which climbs from 850 to 3,500 meters, in the foothills of the Andes of the Central Valley. It is 45 km south east of Santiago, in the Pirque area.

You can enjoy the beautiful landscape of the Río Clarillo valley, which waters the surrounding villages. There are well-forested mountains, and the waters of the river flow between curious rock formations.

The most interesting aspect of the flora is the forest of the so-called hard-leafed (sclerophyllous) trees, since this reserve is the last refuge of these species in the Zona Central. Among these species are the peumo, litre, lun and quillay.

Interesting fauna include the torcaza, or Chilean woodpigeon, which is danger of extinction in this area, and the Chilean iguana.

A visit is to be recommended at any season of the year. There are picnic areas and two excursion trails: Quebrada Jorquera and Aliwen Mahuida. There you may see trees such as canelos and lingues, and groups of vegetation of other species.

The reserve has picnic areas, interpretative trails and an Environmental Information Center.

To get to the this reserve from Santiago, head out on Avenida Vicuña Mackenna towards the south. When you get to Puente Alto the street chanes its name to Avenida Concha and Toro; continue along this road until you reach a T-junction. Here you should turn right and continue for about 2 km until you reach the entrance to the El Principal sector, which is also signed for the reserve. Then continue following the signs for the reserve.