Nobody saw the painters at work, so everything we say about the rock art of eastern Spain is inference, and the inferences have changed over the years. The shelters of the Vero valley hold two broad families of images, as elsewhere in the region: naturalistic figures of people and animals, often in red, called Levantine art, and later, simpler, more abstract signs known as schematic art. The first is usually attributed to hunter-gatherers and the second to farming communities, though the dating is still debated, and many specialists are cautious about exact numbers.
That caution is a good thing to carry with you into the landscape. The cliffs above the Vero are weathered, honey-coloured and pocked with overhangs, and standing under one, you can see how such a shelter would work: out of the rain, facing the light, with a view over the river. What people did there, and what the images meant to them, is a matter of theory, and local museums and guides are a better source than a roadside sign.
The valley is a very pleasant place to ride. The road from Barbastro rises gently along the river, with the cliffs closing in, and beyond Alquézar the lanes climb and twist through olive terraces and oak scrub. Bends are often tight, and gravel is common, so ride within your sight. The country is drier than it looks, and in midsummer the heat bounces off the rock, so keep to the cooler hours.
Barbastro, about twenty kilometres from Alquézar, is the nearest town with fuel and services, and Alquézar has cafés and a few bars for lunch. The local lamb, olive oil and Somontano wine are all worth trying. A short walk from the village leads to viewpoints over the gorge, and the walkways along the cliff are an easy way to see the river from above.
April and May, when the hills are green and the river runs fast, are the best months.