The 'giant's kettles' at Los Pilones were formed by the swirling action of stones trapped in circular depressions within the granite riverbed.
The reserve contains the Cuerda de los Infiernos, which marks the highest point of the Sierra de Tormantos.
The area is home to the rare Lusitanian salamander, a species endemic to the Iberian Peninsula.
The river's temperature remains significantly low even during summer due to the high-mountain snowmelt origins.
The reserve acts as a vital migratory corridor for bird populations moving between the Gredos mountains and the plains of Extremadura.
Reserva Natural Garganta de los Infiernos is a protected nature reserve in the Jerte Valley of the Sierra de Gredos range. The site is best known for 'Los Pilones,' a series of giant's kettle rock pools carved into granite by glacial erosion and river currents. The reserve features significant elevation changes, ranging from 600 meters to 2,200 meters at the Cuerda de los Infiernos peak. The area serves as a habitat for Spanish ibex (mountain goats) and various raptor species. Vegetation includes riverside forests of alders and ash, transitioning into Pyrenean oak forests and high-altitude pastures. Visitors access the main geological formations via a well-marked circular trail. It is part of a larger Natura 2000 network site. The reserve's hydrological system consists of numerous streams feeding into the Jerte River.
The elevated viewpoint overlooking the series of granite basins at Los Pilones.
Wear sturdy, closed-toe hiking shoes with good grip, as the granite rocks near the pools can be extremely slippery.
Bring sufficient water and sun protection, as large sections of the trail leading to the pools offer minimal shade.
Visit during the shoulder seasons to avoid overcrowding at the popular Los Pilones swimming areas.
Do not attempt the full mountain circuit without proper navigation tools, as weather conditions can shift rapidly at higher altitudes.
The interpretive center is generally closed on Mondays; parking capacity at the entrance is restricted and often reaches full occupancy early in the morning during peak summer months.
Strictly pack out all trash; swimming is permitted only in designated areas; do not approach or feed mountain goats.
