The name points to engineers, and in this corner of Albacete the likeliest explanation is water. The upper Segura and Taibilla valleys feed reservoirs and canals that supply towns and farms far down toward Murcia and the coast, and the people who built and maintained that system needed houses in a remote landscape. Las Casas de los Ingenieros sits some distance from Nerpio, in a quiet valley of pine, scrub and farmland, with a rock shelter nearby, and the whole area is dotted with painted shelters from the prehistoric past. Other shelters in the area carry the names of the people who first recorded them, a reminder of how recently some of these sites were noticed.
The ride takes you through an empty, beautiful country. The road from Nerpio runs through fields of cereal and almond, then climbs among rock outcrops and wooded hillsides, with long views south toward the Sierra de las Cabras. It is not busy, and for long stretches you will have it to yourself, apart from the odd farm truck. The surface is variable, with smooth sections giving way to potholes and loose gravel on the edges, and the bends are open but sometimes blind. Spring wildflowers, in April and May, are a high point, and autumn light is warm and golden.
Nerpio is about seven kilometres away, and has only the basic services of a village of under two thousand people, so treat it as a place for a coffee rather than a fuel stop. Yeste, nineteen kilometres off, is a larger town with more shops and a petrol station, and Moratalla is the major centre, a longer drive. Fill up before you leave and carry water.
Visitors tend to come for the rock art, but the valley's greatest asset is its quiet. You will hear sheep bells, the wind in the pines and a distant tractor, and not much else. Park off the road, walk a short way up the slope and let the silence settle. Look for the shelters only with guidance and respect, because the paintings are very old and cannot be replaced.