Still one of Portugal’s wildest landscapes, this 264-sq-km natural park shadows the Rio Tejo and the watersheds of three of its tributaries. While not aesthetically remarkable, it shelters some of the country’s rarest bird species, including black storks, Bonelli’s eagles, royal eagles, Egyptian vultures and griffon vultures.
The Centro Interpretação Ambiental in Castelo Branco provides a great introduction to the area.
The best-marked hiking trail, the 10.5km Rota dos Abutres (Route of the Vultures), descends from Salvaterra do Extremo (60km east of Castelo Branco) into the dramatic canyon of the Rio Erges.
Drivers can get a taste of the park’s natural beauty by following the unnumbered road between Monforte da Beira and Cegonhas (southeast of Castelo Branco), which passes through a beautiful cork-oak forest on either side of the Ribeira do Aravil. It doesn't appear on all maps: pass through Monforte da Beira if coming from Castelo Branco, and turn right after 2km. Alternatively, a signposted turn-off to the park just short of Monforte takes you down a rough, circular route through part of the park, but the way is not well indicated.