The Marathon des Sables is the world's toughest race. This man veered 291km off course — and survived
To understand the intensity of the Marathon des Sables, we need to look at the numbers: a six-day race, winding 251 kilometres through the Sahara Desert, with a midday sun that can push temperatures as high as 50 degrees Celsius.
That's like running six marathons in a hot oven, with 10 kilograms of food and gear strapped to your back.
This year, 47 per cent of runners dropped out before the end of the race.
For those who do stumble across the finishing line — blistered, dehydrated and sometimes hallucinating — they can proudly say they completed one of the toughest endurance races in the world.
However, only one man can say he lost his way during a sandstorm, veered almost 300km off-course and emerged a week later with an incredible tale of survival as well as a new nickname: The Robinson Crusoe of the Sahara.
"While I was out there all those days, wandering alone, I became like an animal, a desert creature that lives by the rules of the sun and behaves entirely on instinct," Mauro Prosperi would tell Men's Journal four years after that fateful race.
"Every thought, every movement of my body, was devoted to surviving. I repeated to myself, 'Do not surrender'."
This is how a 39-year-old Italian Olympian says he survived 10 days in the desert — and why one man insisted it was all a lie.
These days, up to 1,200 people compete in the Marathon des Sables, all of them carrying GPS beacons.
The race is monitored from two helicopters, with 45 medical officers nearby and 120,000 litres of drinking water provided at checkpoints along the route.
However, in 1994, things were a little different.
Prosperi, then a police officer, was one of only 80 entrants in the little-known race.
"A good friend said to me, 'There's this amazing marathon in the desert, but it's very tough'," Prosperi told the BBC in 2014.
"I love a challenge, so I started training immediately, running 40km a day, reducing the amount of water I was drinking to get used to dehydration. I was never home."
Prosperi said he had to sign a form with instructions on where race organisers should send his body should he die: back to his wife, Cinzia, in Sicily.
He promised her the worst thing that could happen to him out there was a little sunburn.
For a while, he was right.
Prosperi covered 96km of sand dunes, salt beds and rocks in three days.
On the fourth and longest day of the race, he was placed seventh and was starting to wonder if he had a shot at winning.
But he didn't realise a monster was headed his way.
When strong winds blow over a desert, tiny particles of sand begin to vibrate before they're whipped into the air.
A sandstorm can reach heights of 15 metres, travelling at speeds of up to 40 kilometres an hour.
Inside the dark, howling centre of a storm, sand lacerates the skin, eyes and throat.
"I was swallowed by a yellow wall of sand. I was blinded, I couldn't breathe. The sand whipped my face — it was like a storm of needles," Prosperi told the BBC.
Fearing that he could be buried in sand and unwilling to give up his position in the race, he kept moving.
This was against the advice of race organisers who had instructed runners to stop and take cover in a sleeping bag if a sandstorm enveloped them.
After eight hours trapped in the storm, Prosperi found himself suddenly, palpably alone in the still desert night.
He slept in the dunes, figuring he would find his way to a checkpoint with his compass and map in the morning.
However, when he woke up, the storm had transformed the landscape into something unrecognisable.
"After running for about four hours, I climbed up a dune and still couldn't see anything," he said.
"That's when I knew I had a big problem."
When he failed to show up at a checkpoint by morning, the Marathon des Sables organisers knew they were in a different kind of race.
They had to find Prosperi by midday or he would be out on the sand in sweltering heat with little water.
First they drove the dunes in Land Rovers. Then they sent up a helicopter to search from above.
The Moroccan military joined the hunt, along with Bedouin trackers.
But the Italian runner appeared to have vanished with the storm.
He was out there, sitting alone on a high dune, waiting with a backpack full of dehydrated food, a compass, a knife, a sleeping bag and a half-empty water bottle.
On his second day alone, he heard the low whirr of a helicopter and his heart leapt.
Prosperi let off his one flare to get the pilot's attention.
"It was flying so low that I could see the pilot's helmet, but he didn't see me — he flew right past," he said.
"That night I urinated into my water bottle and saved it. I said to myself, 'I will drink this if I need to'. I ate a Power Bar and fell asleep on the high dune."
The next day, Prosperi woke up to find two vultures circling the skies above him.
Staggering through the desert, he looked for something, anything, to help him stay alive.
In the distance, he spotted a strange shimmering structure.
It was a marabout shrine, an ancient structure that likely served as a tomb for the remains of an Islamic holy man.
"Up in the tower, I spied three bird's eggs in a nest and ate them," he told Men's Journal.
"I found a wooden pole and went outside to hang an Italian flag on it in case someone were to fly over. Then I sat out the day in the shade of the shrine."
As the days passed, his rations dwindled to nothing and he looked upwards to the bats hanging from the eves.
"I decided I would eat them raw, because cooking them on my portable stove would only dry them out, and I knew that moisture was what I needed most of all," he said.
"So I wrung their necks off and sucked. It was a repellent thing to do, but I was crazed with hunger."
On his fourth day alone, Prosperi heard the distant whirring of hope; a plane was flying overhead.
He set his backpack on fire in the hope that the pilot would see the smoke. He wrote "SOS" in giant letters in the sand.
But those in the plane did not spot him and the aircraft disappeared across the horizon.
"When the plane headed away from me, I said to myself, 'There goes my life'," he said.
With no water, no food and no hope, Prosperi made a decision: this little tomb would also be his final resting place.
He scrawled a note to his wife Cinzia on the wall of the shrine, begging for her forgiveness.
In that moment, the decision to end his life felt entirely reasonable.
To die of thirst was a slow and agonising way to go, and authorities were likely to find his remains there.
Without a body, Cinzia would not be able to claim his police pension for 10 years.
But when his attempt did not succeed, Prosperi said he soon "came to my senses".
"I realised that the marathon was moving on, that I couldn't rely on the race officials to save me," he said.
"I decided I must confront the desert myself."
Determined to survive, he now moved through the desert like he was part of its ecosystem.
He licked the dew off rocks, squeezed moisture from plants, hunted for scarab beetles and snakes, and slept half-buried in sand to keep warm at night.
After eight days in the desert, he came across an oasis.
"Really it was only a large puddle, a mirror of water in a wadi," he told the BBC.
"I threw myself upon it and gulped with abandon, but I could hardly swallow.
"I couldn't hold anything. I found I had to take tiny sips, one every 10 minutes."
Finally replenished, Prosperi kept walking with purpose.
The first sign of life was goat droppings. Then he saw human footprints in the sand.
Finally, he came across a young girl, who screamed at this skeletal figure in dirty spandex staggering towards her.
"I was a skeleton. My eyes had sunk so far back into my skull, I couldn't see them," he said.
But the girl, part of a caravan of nomadic Tuareg, found other members of her tribe who brought Prosperi goat milk and mint tea.
He was saved.
After he was drawn to the Sahara by the challenges of the Marathon des Sables, Prosperi faced a frightening new set of numbers.
Ten days after setting off from the start line, he was found 291km away in Algeria.
He returned to the world weighing just 44 kilograms.
His liver was close to failure, and it took hospital staff 16 litres of intravenous fluids to bring him back from the brink.
While he was hailed a hero in Italy, some claimed that Prosperi was a fraud.
"His story is a fabrication. He will have you believe he is Superman," Patrick Bauer, the founder of the Marathon des Sables said in 1998.
"It is physiologically impossible for a man to travel more than 200km in the desert without water. This is a supernatural act," he said.
Bauer speculated that Prosperi was lost for a few days, but perhaps the Taurag found him earlier than he claimed.
"He thought he could make a killing out of this if he prolonged his ordeal. He thought he could sell his story to the tabloids. He aspired to be the star of his own movie," Bauer claimed.
Prosperi has strenuously denied Bauer's accusations.
In 1995, a documentary crew returned to the shrine where Prosperi sheltered for several days and found some of his belongings, along with bat skeletons.
And a doctor who studies the effects of harsh environments on the human body believes Prosperi's story.
"Mauro didn't lie," Dr Kenneth Kaumler wrote in his book, Surviving the Extremes.
"His body provides compelling testimony to the kind of damage the desert can inflict and, at the same time, evidence of what the body can sustain when pushed to its extremes."
Two years after his ordeal, Prosperi felt well enough to return to his passion: endurance running.
Determined to finish what he started, he ran the Marathon des Sables. He has now completed the race six times, placing 13th in 2001.
While he was alone and frightened in the Sahara, he also fell in love with its stark beauty.
"I'm drawn back to the desert every year to greet it, to experience it," he said.
"Those 10 days were as if I was in the womb of the desert.
"And, after that, I was reborn."
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