Menu Hamburger Logo Menu close Logo
Barcelona Travel Hacks home logo

Aigüestortes Vall de Fosca Lakes and Reservoirs

Spectacular 14km circular hiking route via seven glacial lakes in high mountains of Aigüestortes Vall de Fosca using a cable car to climb to Estany Gento

Updated: Sep 2, 2023 by: Barcelona Travel Hacks Views: 455

About Aigüestortes Vall de Fosca Lakes and Reservoirs

Vall de Fosca in the Aigüestortes i Estany de Sant Maurici Parc Nacional is a spectacular hiking route that uses a cable car to ascend to the first of many great lakes that form part of a vast hydro electric power generation complex that is hidden underground within the mountain.

This is a demanding 14Km one-day hike through the high mountain valley of La Vall Fosca. The Vall de Fosca, Dark Valley, is composed of twent-six lakes, of glacial origin. Highlights are Salente reservoir, Panta de Salente , Gento Lake Estany Gento, Tort Lake Estany Tort, Colomina Lake Estany Colomina, Sea Lake Estany de Mar, Sea Lake Estany de Mar, Saburó Lake Estany Saburó and Frescal Lake Estany Frescal.

When walking to Tort Lake you will see the remains of a narrow gauge railway. This was used to mine the granite rock to build all the dams for the lakes to convert the mountain into a power station. The last section of the route from Gento lake to Salente reservoir is along a via verde. Via Verde's are old rural railway lines that have been removed and converted into cycle lanes.

Sallente reservoir Hydro Electric Power Generation

The Sallente reservoir is fed by water from Estany Gento and 26 glacial lakes that feed the Flamisell river. It is what is known as a Reversible Hydro electric plant. Gento Lake is at an altitude 400m greater than Sallente lake. To generate electricity water is dropped in a steep subterranean tube under pressure of gravity to turn turbines at the height of Sallente lake hidden inside a chamber within the mountain. Valves at the top open to allow water to rush into the tube when electricity is in demand. When electricity is at a surplus (at night) water is pumped back up to the top lake (Estany Gento). This is what is called a peeking generator (or water battery) to provide a boost to the electricity grid in times of high demand.

The power plant within the mountain is closed to the public and does not offer guided tours. The only evidence of it's existence is a large substation at the base of the cable car and a mysterious tunnel entrance that drops down a steep incline into the mountain.