The relief is dominated by the Serra de Água de Pau, which includes a caldeira occupied by the "Lagoa do Fogo" ("Lake of Fire"). The highest elevation is Pico da Barrosa at (overlooking "Lagoa do Fogo") or Monte Escuro at ; this volcanic massif also extends to the plateau of Graminhais, by the eastern border with Nordeste, where the Pico do Salto do Cavalo has a well known lookout. The volcanic geology, associated to the occurrence of many springs in the foothills, have been responsible for the fast creeks flowing in deep ravines, one of which gave its name to the town. Other volcanic manifestations in the area are fumaroles, such as "Caldeira Velha" or "Caldeiras", and mineral hot springs at Lombadas, Gramas and Ladeira da Velha.