Mountain range of a Groba Nature · Oia, Baixo Miño, Pontevedra Image of Oia, not of the place itself. The serra da Groba is a coastal granite massif of some 50 km2 that runs north-south through the concellos of Baiona, Oia and O Rosal, separating the sea from the Minho valley, and reaches its highest point at the Alto da Groba, at 662 metres. It is home to the largest concentration of free-roaming Galician-breed horses, which graze among gorse, heathland and the peat bogs where the rare herba das malladas grows. Petroglyphs abound in its surroundings, with reticulated, spiral and labyrinth shapes, among them those of Auga dos Cebros, in the parish of Oia, which depict boats probably of Phoenician origin; navicular muíños (boat-shaped mills) and numerous mámoas (burial mounds) are also preserved. Photo: User:Paradanta (CC BY-SA 2.5 es) What to see and do in Oia