Ruta 40

The RN40 runs the length of Argentina along the eastern side of the Andes, more than five thousand kilometres from the Bolivian border in Jujuy to the far south of Santa Cruz, crossing eleven provinces, dozens of rivers and mountain passes over four thousand metres. It is less a single road than a thread linking wildly different countries: the coloured desert and puna of the northwest, the vineyards of Cuyo, the volcanic south of Mendoza, the lake district of Neuquén and Río Negro, and the empty windswept steppe of Patagonia where settlements can be two hundred kilometres apart. Much of it is now paved, though gravel sections remain, particularly in the far south, and the road has become a journey in itself for drivers and cyclists.

What you actually see

• The northwest - puna, coloured rock and high passes in Jujuy and Salta.
• The wine country - vineyards and oasis towns through Cuyo.
• The lake district - the forested Andean corridor in Neuquén and Río Negro.
• The Patagonian steppe - immense empty distances with rare settlements.

When to go

November to March for the Patagonian and high-altitude sections, when passes are open and daylight is long; winter closes parts of the road with snow. The northern sections work year-round, though summer rain can cut them.

Honest expectations

Distances between fuel, food and lodging are very long in the south, and running on a half tank is a mistake. Gravel sections damage tyres and windscreens, and the Patagonian wind is a constant, tiring force. Doing the whole road takes weeks, and most travellers drive a section rather than the length.

Nearby

The road links Cafayate, Mendoza, Bariloche, El Chaltén and El Calafate among many others.