The Speed Project Atacama: The rebel race across a desert

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The Atacama Desert, Chile.

The driest non-polar desert on earth.

Average annual rainfall? Under a millimetre, with some regions waiting decades between sparse showers.

The temperature swings from 30C in the day to below freezing at night.

It is a region so barren and devoid of life that Nasa regularly uses it to simulate and practise for their landings on Mars.

It sounds like a tricky enough place to organise a Parkrun, so where do you even begin organising a 310-mile non-stop ultra-marathon?

If your name is Nils Arend - and your race is The Speed Project - the answer is simple.

You don't.

Until a voice rises above the rest.

It's the softly spoken German-American fusion accent of the man who has convinced everyone to be here.

And, more importantly, to leavehere, on foot, and run across the Atacama Desert, alongside the main highway, to the 'finish line' at San Pedro de Atacama, some 500km away and at an altitude of 2,400m.

Like the American version of The Speed Project (TSP) from Los Angeles to Las Vegas which made organiser Arend's name, this race has no prize money, no rules, no set route and no website.

And, like LA-LV, there is no official way to enter.

Invitations and intros come via Arend's WhatsApp, and the event itself is unsanctioned and entirely unsupported.

Unsupported, perhaps, but certainly not under the radar.

Among the 90 runners - broken down into 15 teams of six - are former Olympians, a high-profile American TV presenter, the so-called "real-life Forrest Gump" William Goodge, who this summer became the fastest Briton to run across America,, external and former women's international footballer Daniela Andrade, who has run the length of Chile solo.

It's 4am in late November in the Chilean beach city of Iquique.

Ninety runners from all over the world are limbering up in a deserted skatepark on the beachfront, 50m from the Pacific Ocean.

The streets, other than a host of stray dogs, are deserted. Apart from the buzz of camera drones flying overhead and the nervous energy of the short-shorted runners milling about, it is strangely quiet.

When those runners left the 'start line' - an entirely arbitrary point on one edge of the skate park where Arend elected to stand when he got out of his pick-up truck a few minutes earlier - they had zero support from TSP organisers.

Unsupported racing is not a new phenomenon in running, or indeed in other sports like ultra-distance cycling.

For example, The Trans Continental (TCR) is infamous in the world of cycling as a brutal, yet beautiful 4,000km solo race across Europe in which accepting help of any kind means disqualification.

But even in races like TCR each rider has a tracking device and there are checkpoints to ride through and monitor the welfare of the field.

Arend already adamantly shied away from any such checks and balances for The Speed Project.

With TSP Atacama, he pushed the boundaries and runners' comfort zones even further.

In the pre-race briefing he readily admitted that if his US and Chilean races were compared to cats then "LA-LV would be a domestic cat, while Atacama would definitely be a tiger".

The TSP Atacama course, or what passes for it without an official route, includes only one option to resupply.

As a result, the assembled teams all have two vehicles in tow.

Mostly US-style flat-bed trucks, they are laden down with enough food, fuel and, crucially, water to sustain six runners and their support staff for one, long continuous run across a moon-like landscape.

One runner in each team of six has to be moving at all times alongside the one road that traverses this hugely inhospitable environment.

Number one runner and captain for one team, and a standout names in the race, is Roberto Mandje.

Mandje is an Olympic track and field athlete, competing for Equatorial Guinea at Athens 2004.

Later in his professional career, Mandje raced at the World Cross Country Championships and the World Trail Racing Championships.

But the track was his first love, and specifically the 1500m.

Which is handy, because his team's policy, and that of most of the other 14 teams, was little and often.

In essence, the favoured tactic for the fastest way to clock 500km was frequently swapping runners in and out and breaking the distance down into two or three kilometre sections each.

On repeat.

For nearly two days.

In theory, each leg sounded pretty achievable. About half a Parkrun at a time.

But, as Mandje attests, in the middle of the night, without any sleep and with a day's running already in your legs, The Speed Project got serious.

Mandje made his living racing the 1500m at top speed, recovering with ice baths and complex warm-down routines.

In Chile, with recovery taking place while cooped up eating cold pizza in the back of a pick-up truck, he found himself suddenly reduced to walking parts of the TSP route.

"What made it really, really challenging is you're running short intervals and then getting into a van, getting stiff, getting tired, then in another hour you're jumping back out to run again," says Mandje.

"After two days that starts to wear and tear on you - especially for those overnight legs when you're out there with your thoughts and accumulated fatigue.

"The hardest point, somewhere on day two, I just hit a 30km stretch where I struggled. Each time I got out of the vehicle I had to start each leg as like a shuffle or a speed walk.

"It was also the point of the journey where you're a long way from the start, so you can sniff the finish but you also know there's a long way, and a lot of climbing, to go.

"But hitting a rough patch was part of the beauty of it."

Long before Mandje's personal crisis, the race itself was thrown into a wider crisis.

Much more serious than pain in the legs, this was related to the strong arm of the law.