When you’re navigating Argentina’s Wild West it helps if you have a reliable steed. Otherwise, as the roadside shrines in Salta province warn, you can become vulture food. I contemplated this as I coaxed my ride, a four-wheel-drive Land Rover, up a ridge so sheer it threatened to tip us backwards. But the SUV clung to the rock like a mountain goat, raising its computer-controlled suspension to inch us up and, amazingly, over.

I’d never driven a 4x4 on road before, never mind navigating rivers, boulders and expanses of desert where, if you slow down, your wheels sink (my chaperones had towropes). I needn’t have worried. The vehicle did almost all the hard work and the Land Rover people leading our convoy warned us of impending hazards via walkie-talkie. They even told us which setting to choose on our vehicles’ Terrain Response dial, which sets clever electronic controls (that’s about as technical as I get) to cope with surfaces ranging from sand to ice. The reason I sank in the desert was I’d set it to “rock crawl”. Doh.

In one river valley we met two Indian farmers: Ricardo Cruz, 30, and Santos Ricardo, 33. They said they were “indigenous”, which was as ethnically specific as most locals got. The northwest was once home to several Indian tribes, but colonisation, first by the Incas, then the Spanish, tumbledried the gene pool and the culture.

Spanish is the lingua franca, and even remote settlements are in thrall to two major religions: Catholicism and football. Dusty pitches and simple, proud churches abound. Santos and Ricardo are the valley’s only residents. Sometimes they don’t see their families for months, as they have to work every day. But they had found time to take an offering of flowers to Pachamama, an Inca goddess.

They’d bury the flowers at a shrine, and Pachamama would take care of their problems. Santos, however, had an alternative way of alleviating his woes. His left cheek bulged with coca leaves, the plant from which cocaine is refined. Possession of small quantities to combat altitude sickness is legal – but Santos had imbibed enough to withstand a space-shuttle flight. His sentences spewed forth like bursts of gunfire. Ricardo, unable to speak without interruption, eventually lapsed into silent, sarcastic mirth.

We drove on, to 5,000 metres above sea level, acquiring some coca at around 3,000 metres as the first signs of altitude sickness – dry throat, dull headache, queasiness – began to bite. I kept a mouthful of bitter leaves: enough to combat the sickness, but not enough to start barking at the moon.

The final leg of the journey took us down the Quebrada del Toro gorge and on to the colonial city of Salta. This was the last chance to savour some of the most ruggedly beautiful landscapes on Earth. The colour palettes are extraordinary. There are flocks of parrots, distant sandstorms and caves with icy stalactites like dragons’ teeth. Small wonder that Argentina has so many churches. Surrounded by this much natural beauty, atheism seems to have missed the point.

How to get there

The 12-night Land Rover trip to Argentina, including accommodation, food, vehicle and domestic flights, costs from £2,800 per person. International flights not included. Tel: 0049 2058 778 090. E-mail: expeditions@landrover-experience.de

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