Parque Provincial Ischigualasto and Parque Nacional Talampaya

Some 80km north of Valle Fértil, the PARQUE PROVINCIAL ISCHIGUALASTO, also known as the Valle de la Luna, or Moon Valley, is San Juan’s most famous feature by far. Covering nearly 150 square kilometres of desolate but astonishingly varied terrain, it can be visited only in a vehicle – either your own or that of a tour operator. For paleontologists, Ischigualasto’s importance is primarily as a rich dinosaur burial ground: two of the world’s very oldest species of dinosaurs, the diminutive Euraptor lunesis and Herrerasaurus ischigualastensis, both dating back some 230 million years, were found here, among many others. The park is also a joy for geologists, as most strata of the 45-million-year Triassic era are on plain view. However, the majority of visitors come simply to admire the spectacular lunar landscapes that give the park its popular nickname, and the much publicized and alarmingly fragile rock formations – some have already disappeared, the victims of erosion and the occasional flash floods that seem to strike with increasing frequency. Cerro El Morado (1700m), a barrow-like mountain that according to local lore is shaped like an Indian lying on his back, dominates the park to the east. A segmented row of rocks is known as El Gusano (the Worm); a huge set of vessel-like boulders is known as El Submarino; a sandy field dotted with cannon-ball-shaped stones is dubbed the Cancha de Bolas (the Ball-court). One famous formation, painfully fragile on its slender stalk, is El Hongo (the Mushroom), beautifully set off against the red sandstone cliffs behind.

The park is in a desert valley between two ranges of high mountains, the Sierra Los Rastros to the west and Cerros Colorados to the east. As witnessed by the mollusc and coral fossils found in the cliffsides, for a long time the whole area was under water. Over the course of millions of years the terrain has been eroded by wind and water, and sections built of volcanic ash have taken on a ghostly greyish-white hue. A set of red sandstone mountains to the north acts as a perfect backdrop to the paler stone formations and clay blocks, all of which are impressively illuminated in the late evening. Another of the park’s attractions is its wealth of flora and fauna. The main plant varieties are the native broom-like brea, three varieties of the scrawny jarilla, both black and white species of algarrobo, the chañar, retamo and molle shrubs and four varieties of cactus. Animals that you are likely to spot here include European hares, Patagonian hares, the vizcacha, the grey fox, armadillos and small rodents, plus several species of bat, frog, toad, lizard and snake. Condors and ñandús are often seen, too, while guanacos may be spotted standing like sentinels atop the rocks, before scampering off.

The entrance to PARQUE NACIONAL TALAMPAYA is 55km down the RN-76 from Villa Unión, and then along a signposted road to the east. Coming from the south, it’s 93km north of Ischigualasto and 190km from Valle Fértil. The park’s main feature is a wide-bottomed canyon flanked by 180m-high, rust-coloured sandstone cliffs, so smooth and sheer that they look as if they were sliced through by a giant cheese-wire. Another section of the canyon is made up of rock formations that seem to have been created as part of a surreal Gothic cathedral. Added attractions are the presence of several bird species, including condors and eagles, as well as rich flora and some pre-Columbian petroglyphs. The park’s name comes from the indigenous people’s words ktala – the locally abundant tala bush – and ampaya, meaning dry riverbed.

Talampaya’s cliffs appear so frequently on national tourism promotion posters and in coffee-table books, you think you know what you’re getting before you arrive. But no photograph really prepares you for the belittling feeling you have when standing at the foot of a massive rock wall, where the silence is broken only by the wind. Even the classic shots of orange-red precipices looming over what looks like a toy jeep, included for scale, don’t really convey the astonishment. The national park, covering 215 square kilometres, was created in 1997 to protect the canyon and all its treasures. Geologically it’s part of the Sierra Los Colorados, whose rippling mass you can see in the distance to the east. The sandstone cliffs were formed at the beginning of the Triassic period, nearly 250 million years ago, and have gradually been eroded by torrential rain and various rivers that have exploited geological faults in the rock, the reason why the cliffs are so sheer.