Above Braga, between the serras of Gerês (to the north) and Cabreira and do Barroso (to the south), is the rocky valley of the River Cavdo and that of its tributary the Rabagão. Numerous dams hold back their deep-blue waters. Heading upriver there are views of a changing landscape, with the wooded slopes of the upper Douro below, and the barren peaks and rocky plateaus of Trás-os-Montes above.