The toughest footrace on earth

The Marathon des Sables is an ultra marathon like no other. It covers 156 miles in the world's most inhospitable desert...the Sahara. It's like running five and a half marathons! It takes place yearly over six days. So if you are looking for the ultimate physical and mental challenge this is for you.It was started by Patrick Bauer in 1986 two years after he traversed the desert on foot and alone. he covered 214 miles in 12 days. Only 23 runners took place in the first one, but by 2009 more than 1000 runners participated.The Marathon des Sables is an ultra marathonThe rules require you are self-sufficient and carry with you on your back everything, except water, that you need to survive. You are given a place in a tent to sleep at night but any other equipment and food must be carried. The water is supplied but rationed and you have minimum and maximum food allowances you can bring and carry. It's the lesser of two evils as in the 50 degree heat, you'll want to be as light as possible, but so fatigued you'll want nourishment. Tough call to make but each year many continue to take up the challenge.Places are sought after and do come at a price. Those who make it to the start line are richly rewarded. Under the scorching Moroccan sun, life-long friendships are fostered through a shared experience of unforgettable days spent running across saltpans, up desert-mountains, through ruined towns and the occasional sand storm.Here's some key facts:

250+ kms (156+ miles) 6 stages over 7 days with a long stage of 80+ kms (52+miles)

Self-sufficient but with water rations and tent supplied. You have to carry a minimum of 2000 calories per day but your pack must be a minimum of 6.5kg and maximum of 15kgs. Runners optimise this according to their size

Temperatures of 50+ degrees centigrade. A lot of runners take up Bikram Yoga in the two weeks prior to help with acclimatising.

Find out more you think of a challenge more gruelling mentally and physically? We'd love to hear what challenges you have undertaken. Leave all comments below.