Image copyright Indra Jaerisch

When Chris Haslam paid a visit to the loneliest man in Argentina he was expecting to find a life as dramatic as the scenery. It wasn't the thrilling encounter he was hoping for.

The interview isn't going terribly well.

I've travelled for four days to Argentina's mountainous north-western corner to talk to a man whom I thought might be the world's loneliest pensioner. It turns out that he's not as lonely as I was led to believe, but we'll come back to that.

This sun-cured, septuagenarian llama farmer is called Don Roberto Placa and he lives on the slopes of an 18,400ft (5,600m) mountain bang in the middle of nowhere. From the broken plastic chair outside his low, sparsely-furnished home, he can see four volcanoes, a shimmering salt desert and, in the distance, against a space-black sky, the jagged spike of the Cerro del Hombre Muerto - the Dead Man's Peak.

The nearest village is three hours away, along a frost-shattered, quake-cracked track that winds through a Dali-esque landscape of glassy walls of lava, sudden-death ravines and toxic lakes of arsenic.

Image copyright Indra Jaerisch

Image copyright Chris Haslam

They call this place La Puna, from the Quechua word for "badlands", and they say it's the place God gave the Devil to show off his landscaping skills. Curiosity as to how, and why, anyone can live in this disturbingly beautiful yet hellish land is what brought me here - but as I mentioned Don Roberto is being wilfully obdurate.

He was born on this wind-scoured slope and has lived here for 74 years, he says. Since his parents died, he's been alone, but life is "tranquilo".

Image copyright Chris Haslam

The thermal variation here is the highest on earth, with temperatures ranging from plus 30C to minus 30C in the space of a single day. It must be tough dealing with that, I suggest.

Don Roberto shrugs. "It's fine."

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What about the pumas? I ask. Yesterday, a German explorer told me how he'd found one of Don Roberto's elderly neighbours - he lives just 55 miles (88km) down the road - bedridden with a broken hip, half-starved and dangerously dehydrated, while a pair of mountain lions waited patiently on his doorstep for him to expire.

"Pumas?" sniffs Don Roberto. "Pussy cats."

And so, in one of the most dramatic landscapes on earth, continues one of the world's most humdrum interviews.

What about food? I ask. "When I run out I go hungry. No problem."

Health? "I pray to God and within three days I'm better."

Loneliness? "People drop by all the time," sighs Don Roberto. "Just eight weeks ago I had a visitor."

Image copyright Indra Jaerisch

Storms, earthquakes, landslides and volcanic eruptions? "I make offerings to Pachamama for protection," says Don Roberto, referring to the Inca goddess.

He leads me around his garden. Watered by trenches dug in the turf from the glacial stream nearby, it sprouts guava, potatoes and avocados.

Don Roberto shows me his pear tree. "Frost-proof," he says before bending with the suppleness of a yogi to dam a channel with a slab of obsidian.

Does he have a radio? No.

TV? No.

Doesn't he get bored? Don Roberto gives me a wearily incredulous look. "Bored?" he says. "I don't have time to get bored."

His daily routine involves tending his garden, praying to God and looking after his small herd of llamas, some of whom are "in the meadow, over the back," he says.

By "over the back" he means a 22-mile (35km) round trip on foot over a 15,000ft (4,500m) pass that's regularly closed by blizzards.

"That's a dangerous hike," I say.

"Not really," replies Don Roberto.

Image copyright Chris Haslam Image caption Don Roberto Placa's home

It's time to play the trump card, the last resort of the inept reporter. It works like this: you make an irresistibly attractive hypothetical proposal in the confident expectation that the interviewee will reject it. His justification of that rejection will then reinforce the story.

"So if the government offered you a brand-new, centrally-heated, air-conditioned apartment in the city of Salta - a two-day drive from here - with running water and a flat-screen TV, would you take it?" I ask.

Don Roberto looks at me like I'm an idiot. "Of course I would," he says.

And there's a reason why this seemingly indestructible old pragmatist would jump at the chance to escape. He's not as alone here as he makes out.

Behind his house, stands another, but in his laconic description of his 30 years of solitude, Don Roberto hasn't once mentioned his neighbour. When I ask, he gives me a look as dark as the storm sweeping in from the Chilean border. He will not discuss the neighbour. The interview it seems is terminado.

That night, in a cold diner in the dusty hamlet of Tolar Grande, 88 miles north, I learn the truth.

Don Roberto's neighbour is his sister, confides the waitress. No-one remembers why they fell out, but they haven't spoken in 30 years.

There's nothing in Pachamama's book of spells it seems, that's more powerful than a family feud.

Image copyright Chris Haslam

Image copyright Chris Haslam

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