Embalse El Yeso is an artificial reservoir situated in the Andes Mountains of the Santiago Metropolitan Region, approximately 98 km southeast of Santiago at an elevation of 2,500 meters above sea level. The reservoir was formed by damming the Yeso River, part of the Maipo river basin, with construction beginning in 1954 and completing in 1964. It holds approximately 250–253 million cubic meters of water and functions as one of the primary drinking water sources for Santiago, serving an estimated 7 million people alongside the nearby Laguna Negra.

The water is notably turquoise in color, a result of glacial mineral content, and the reservoir is surrounded by Andean peaks that remain snow-capped for much of the year. The area covers over 16,000 hectares within what is now managed as a park zone in the Cajón del Maipo.

Kayaking is offered on the reservoir through organized tour operators, with guided kayak excursions departing from Santiago and including equipment such as paddles, spray skirts, windbreaker jackets, safety vests, and first aid support. Windsurfing is also noted as a compatible activity on the water. Fishing is permitted on the reservoir as well.

Access to the shoreline is restricted for safety reasons — visitors are generally limited to viewing the reservoir from the main road or from the dam's viewpoint. The site operates on a managed schedule, with opening hours on Saturdays and Sundays from 8:00 am to 6:00 pm during at least part of the year, and an entrance fee applies. The road to the reservoir is unpaved in its final stretch and requires a 4×4 vehicle. The route passes through San José de Maipo via Route G-25 (Camino al Volcán), with the total journey from Santiago taking approximately 3 hours. The road may be closed in winter due to snow accumulation, making summer the primary accessible season for paddling activities.

Wildlife in the area includes Andean condors, guanacos, and culpeo foxes. The Termas del Plomo hot springs are located further up the dirt track from the dam at approximately 2,900 meters elevation, and the Laguna Negra trail is accessible nearby with a certified guide or tour operator.