Alforfas’ Glacial valley (Vale de Alforfa (Unhais)

Unhais Valley viewpoint is located on the side of the Alto da Pedrice plateau, close to the load chamber of the Pedra Figueira Hydroelectric Central, at an altitude of approximately 1300m. The landscape that covers this point encompasses a panorama that comprises the Unhais valley, upstream from Unhais da Serra, the southern sides of the upper plateau of Serra da Estrela and, to the south, Serra do Açor.

The Unhais valley makes the connection between the Saint Anthony Nave and the foot of the mountain, being located on one of the most extensive geological faults in Portugal. Named Vilariça, this accident extends from Bragança, to Sertã, in the center of the country, reaching a length greater than 250 km. In the upper sector of the valley, on the eastern side, surfaces are visible where the granitic rocks are deeply altered, a phenomenon that shows the displacement of the referred fault. Still in this sector, where the Alforfa stream runs, a tributary stream of the Unhais stream, the valley has a cross-section in a “U” shape and a succession of depressions in the staircase stands out, aspects that reveal the morphology of a valley glacial. Finally, in the sector further up the valley, on the side of Alto da Pedrice, there is an extensive accumulation of granite rock blocks, whose fragmentation results from the mechanical pressure exerted by the freezing of the water infiltrated in cracks in the rocks.