The Basturs lakes are among the few karstic upwellings in Catalonia. Their waters are home to plant and animal species that cannot be found in any other waters in the country. There are paths for visitors and access to a bird-watching hide.
The wetlands of Estanys de Basturs are made up of several karst lakes typical of the Pyrenean foothills, formed by the dissolution of limestone and underlying sulphates and fed by a fairly constant water source throughout the year.
Together with the lacustrine area of Banyoles, that of the Sant Miquel de Campmajor valley and Montcortès lake, these lakes make up the four most significant karst lakes in Catalonia.
Currently the area has two lakes: a larger one which is almost circular with a conical basin, and a smaller one (called Estany Xic), located to the north-west of the first, where it is completely surrounded by crops and partially dried out due to the opening of a drainage ditch. This place is still geologically active and the last upwelling was in the mid 90s. Unfortunately, the hole was plugged and covered over.
The vegetation inside the lakes is surprisingly unique. Over 120 different species of single-celled algae have been identified in the larger lake and around eighty in the smaller one. Moreover, in the large lake a single-celled alga has been found (Ceratium cornutum) that does not live anywhere else in the world. Likewise, on the surface we can see a carnivorous plant (Utricularia vulgaris) that does not have roots and that lives floating on the surface of the water.
There are walkways that allow you to visit the lakes, as well as a bird-watching hide.