During the Upper Pleistocene age, over 100,000 years
ago, an impressive glacier with ice tongues of more than 20 kilometres
in length gave rise to what is currently known as the Lago de
Today, its 318 hectares of surface area and depth reaching 51 metres make it the largest lake in the Iberian peninsula.
Surrounding the Lago de Sanabria, there are abundant forests formed by Pyrenean oaks. There are also interesting clumps of holly and yew trees while birch trees and alders are plentiful in the banks of the rivers that descend from the summits or link the different lakes contained within the natural park.
The woods are substituted with thickets of escabon, buckthorn and heather. In Sanabria there are also endemic species: the Carqueixa Sanabresa and the Geranium bohenicum. In terms of fauna, they are worth of mention the golden eagle, wolf, roe deer, Bocage's lizard and Seoane's viper.
In addition to is high environmental value, the
Parque Natural de Sanabria offers valuable historic, artistic
and cultural resources. Along with the interesting Romanesque
monastery of Santa María, situated in San Martín
de Castañeda -headquarters of the Natural Park Interpretation
Centre-, especially notable is the collection of urban monuments
in Puebla de Sanabria.