This hike is featured in all the guidebooks that mention the most beautiful lakes of the Pyrenees. Hidden high up in a wild mountain range, Lake Er is a prime destination for all those who love challenging hikes surrounded by rich, well-preserved nature.

The Pyrenees is an area which is extremely rich in biodiversity. There are more than 2,500 plant species, i.e. more than 40% of the plant diversity of metropolitan France, on barely 0.5% of the territory. The Pyrenean flora has developed numerous adaptations that allow it to colonise the highest altitudes, where the climatic conditions are the most challenging. In the Lake Er area, you can see the remarkable beech and fir trees and elder orchids.