The name Valdebría points to a valley, and the ground here bears it out: a fold in the hills above the Sil where the land drops away in terraces and the old Roman workings leave their pale scars on the slopes. This stop is about the scale of what happened here. In the first and second centuries, tens of thousands of people, many of them enslaved or forced labourers, worked the gold-bearing gravels across the north-west of the peninsula, and the estéiles are what they left behind.
Standing on the spoil, you see how the Romans worked with the land rather than against it. The channels they cut, the corrugas, still trace the contours along the hillsides, and some can be followed on foot as faint grassy trenches. The surrounding country is covered in chestnut, oak and heather, which is why the colours in October are so rich, and why the place smells of damp leaves and woodsmoke.
Riding in the region is rewarding but needs focus. The roads wind along the Sil and its tributaries, narrow and sometimes bumpy, with sharp bends where small streams cross. Rockfall and gravel are possible after storms, and fog can settle in the valleys in autumn and winter. Livestock sometimes share the road, and so do the odd logging trucks.
Puente de Domingo Flórez is the nearest village of any size, with fewer than two thousand people, and there you can find a bar, bread and a few basics. For more reliable fuel, head toward Ponferrada or Cacabelos, a good half hour on these twisting roads. The ride that continues from here is aimed at the cathedral of Mondoñedo in northern Galicia, a long way across mountains and valleys, so make an early start and keep an eye on the clock. The weather in the hills turns quickly, so carry a waterproof, and treat every unmarked junction as a chance to look around.