The Yukon Arctic Ultra is a non-stop multi-day race that takes place in Canada at the beginning of February each year. The race was founded in 2003 and has run every year since except in 2010.
The race is billed as the toughest ultramarathon in the world. The athletes have to carry all of their supplies. Temperatures can drop to -50 degrees plus wind chill.
There are races over 100/300/430 miles. The race begins in Whitehorse, Yukon and follows part of the Yukon Quest, a 1,000-mile International Sled Dog Race. The longer races have two other disciplines available: mountain biking and xc-skiing.