Rewilding Portugal: the valley that waited 400 years for the cows to come home

The rewilding scheme visited by Phoebe Smith is creating a wildlife corridor along the Côa River valley, linking it with the Douro valley (pictured). Photograph: HagaiLeal/Getty Images

To the outside world we must have been a very odd sight. A group of 20 people standing on the sloping granite boulder-strewn hillside of Ermo das Águias in Portugal’s Côa valley, taking photographs and whispering in awe at the sight of what appeared to be an enclosure of brown cows.