By Milly Stilinovic06 Oct 2016Race around the world through the toughest marathons one can face (and potentially survive). So, you think you’re tough enough to take on the gruelling gauntlet of these three marathons? Listen up, tough mudders! You may be in peak health and can run like the wind but nothing tests your endurance and stamina more than a marathon. Add “ultra” to the mix and you know you’re faced with extreme temperatures, endless lengths and despicable heights. The longest Sweltering 50 degree heat will accompany you the entire length of the 248 kilometre, six-day race through the Sahara. The Marathon des Sables, takes place in Southern Morocco. Runners have been known to complain about the feeling of endlessness. There’s also the difficulty of not being able to run in certain parts as many areas are covered in fine sand that seems to sink the heel of your shoe. The trek isn’t to be taken lightly, either. At least three runners have perished on this gruelling track. The highest Forget smashing up the endless stairs of the Empire State Building, the marathon that will take you up dizzying heights is the 42 kilometre Tenzig-Hillary Everest Marathon. The marathon starts from the Everest Base Camp (5364m/17,598ft) and finishes at Namche Bazaar (3446m/11306ft). You’ll be trekking through sherpa villages and spending nights acclimatising to the cold weather conditions. Sounds like a stroll in the park? No, sir! You’ll have to head to Nepal three weeks before the event to build up your endurance. Without it, it’s extremely questionable whether you’d reach the summit to take in the picturesque panorama of the Himalayas. The coldest Many athletic-types claim they can endure cold temperatures and love the winter. How about a whole -39 degrees of winter? The Siberian Ice Marathon, held each January in Omsk, Russia, is certifiably the coldest marathon in the world. The fact that the Siberian Ice Marathon is only a half marathon may deter puritans from engaging in the competition. However, it is 21 kilometres of running through snow and harsh winds. Ever taken on an ultra marathon? Tell us about it! Other stories you may like VOTE NOW: The 2018 KARRYON AWARDS are here – Have your say and WIN! New women-only tours just part of Intrepid Travel’s equality plan Welcome to a new era of KARRYON: New GM, new logo & new ideas!