One of the best known and most beautiful places of Serra da Estrela, Poço do Inferno (Inferno well) is a small waterfall 10 meters high, formed by Ribeira de Leandres. At 1080 meters, this waterfall can freeze in the harshest winters. Leafy trees lead the way to Poço do Inferno. giving it a singular charm, particularly in Autumn. On the road, just above the waterfall, there is a small viewpoint.