The western boundary of Argentine Patagonia and the border with Chile are formed by the southern reaches of the Cordillera de los Andes, the world’s longest mountain chain. These peaks are the feature that draws most visitors here, luring them along with a ring of beautiful lakes and a national park, albeit not as famous or as breathtaking as Los Glaciares. The nationally renowned RN-40 (often simply called “La Cuarenta”) zigzags up this mountainside swathe of inland Patagonia; indeed it hugs the Andes all the way from the southern tip of the mainland to the Bolivian border in the far north. Most access roads for visiting the region run west from the RN-40: to the wild trekking areas around lakes Posadas and Pueyrredón and into Parque Nacional Perito Moreno. The main exceptions are the major archeological site of the Cueva de las Manos Pintadas in the canyon of Río de las Pinturas, just east of the RN-40; and the oasis town of Sarmiento, a very useful stopover for anyone travelling farther up to the Lake District.
The region’s scenery is predominately dry and flat, though some slopes are densely cloaked in southern beech woods, with a narrow fringe of scrubland separating forest from steppe. It’s in these areas that you stand your best chance of seeing the area’s outstanding fauna: condors, and perhaps even a puma or huemul. As for flora, the brush looks dreary and anonymous for most of the year. Some bushes liven up considerably in the spring, however, not least the thorny calafate, which blooms with a profusion of yellow flowers, and the lengua de fuego with its gloriously bright orange flowers like clam shells. The RN-40 also passes harsh meseta, rocky outcrops, patches of desert and the occasional river valley, usually accompanied by boggy pasture and lined in places with willow and poplar. Here you’ll find the few people who live along the route, where old traditions and an unhurried pace still reign.