Fans of the Road Runner cartoon will feel oddly at home among the red sandstone rock formations in this rarely visited national park. The park comprises 1500 sq km of canyons and dry lake beds among the Sierra de las Quijadas, whose peaks reach 1200m at Cerro Portillo. Recent paleontological excavations by the Universidad Nacional de San Luis and New York’s Museum of Natural History have unearthed dinosaur tracks and fossils from the Lower Cretaceous, about 120 million years ago.
From the park entrance, a 6km dirt road leads west to a viewpoint overlooking the Potrero de la Aguada, a scenic depression beneath the peaks of the sierra that collects the runoff from much of the park and is a prime wildlife area.
Hiking possibilities are excellent, but the complex canyons require a tremendous sense of direction or, preferably, the assistance of a local guide (call the national park ahead of time to arrange one). Even experienced hikers should beware of summer rains and flash floods, which make the canyons extremely dangerous.
Bring your own food and drinks, as there are no places to eat or to buy provisions inside the park. There used to be a shady campground, but it has closed for refurbishment, without an official reopening date. Call the park office to see if it has reopened.
Despite the shortage of visitors here, access to the park is excellent: buses from San Juan to San Luis pass every hour or so, though you might have to ask them to stop. Buses drop visitors at the park entrance just beyond the village of Hualtarán, about 110km northwest of San Luis via RN 147 (San Juan is 210km to the northwest).
It’s sometimes possible to catch a lift from the park entrance to the viewpoint overlooking the Potrero de la Aguada.