The Pla de Petracos is a plain of limestone and scrub above the Vall de Castells, and it has one of the best-regarded sets of rock-art shelters in the whole Valencian region. The name means something close to a plateau of stones, which is exactly what it looks like: bare ledges, kermes oak, rosemary and pine, with tilted strata of grey rock and caves at the foot of cliffs. It is only four kilometres from Castell de Castells and a little more from Vall d'Ebo.
Getting there means riding the winding road up from the coast. Callosa d'en Sarrià and the Guadalest valley are the usual gates, and from there the road climbs through terraces of almond and olive before reaching the high ground. The hairpins are tight but the views are long, and the road is well used by cyclists, so keep a careful line. There is almost no heavy traffic. Go early in the day for cooler air and for good light on the cliffs.
What makes Petracos interesting is that it holds both the naturalistic Levantine art and the later schematic tradition, so you can see how painted styles changed from lively hunting scenes to stylised signs. The schematic figures, with their stick-like humans and abstract symbols, belong to farming communities of the Neolithic and later, while the Levantine panels are generally thought to be older. Standing in front of them, you realise that people lived, painted and returned here for thousands of years.
Remember that the shelters are protected and often require advance arrangements or a guide, so do not expect to wander in. The nearest large town is Pego, eleven kilometres away, with fuel, supermarkets and the wetlands of the Marjal de Pego-Oliva, a nature park of rice fields and reedbeds that is excellent for birds. The villages around Petracos have bars but not always pumps, and Vall d'Ebo is a fine place to learn how an entire valley was depopulated in 1609.