Vale de Moinhos means valley of the mills, and the name is a good clue to what this ground was once for. Small streams run down from the plateau toward the Côa, and wherever the water ran fast enough, farmers built stone mills to grind their grain, many of them now roofless and swallowed by rockrose and broom. It is a quiet fold of schist hills a few kilometres south of Vila Nova de Foz Côa, in the north-east of Portugal, with the big Douro country just beyond.
The Côa itself is the thing to understand. It rises in the hills near the Spanish border and flows north to the Douro, an unusual river in Portugal because it runs against the grain of the country, and for much of the Middle Ages it marked a frontier. The Treaty of Alcañices in 1297 settled much of the border here, and the castles of Almeida, Castelo Rodrigo and Marialva stand as relics of the long argument. But the real surprise of the valley is much older. In the early 1990s engineers surveying for a dam noticed carvings on the rock faces, and archaeologists realised they were looking at one of the largest open-air collections of Ice Age art in the world. A public campaign, reaching into a national election in 1995, ended with the dam's cancellation the following year, and the valley is now a World Heritage site.
The riding in this part of the country is about space and light. Narrow roads follow the contours of the valleys and cross small stone bridges, with farms hidden among almond and olive trees, and long views over rounded hills that are brown in summer and green in spring. Traffic is almost nil on the minor roads, and the surface can be broken and patched, so keep your speed down on blind bends where gravel collects. Summer afternoons are very hot, with temperatures in the high thirties common, and the best time to be out is in the morning. Wild boar and deer cross at dusk, and the occasional flock of sheep takes over the road.
Vila Nova de Foz Côa, about five kilometres away, is where to find fuel, food and a bed, with Torre de Moncorvo to the north. Cafes in the town serve a strong coffee and excellent pastries, and the town is the starting point for the museum and rock art visits.