This is a race that every ounce counts since you have to carry everything you need on your back and run the 250 km.
Marathon Des Sables always has a long stage that will be at least a double marathon distance. The long stage has become a legend in itself. Runners will take off in the morning of Day 4, into the dusk and then the dark, many not finishing the 80+km till well into the next day. This is way longer than any of my longest runs - a marathon distance. And the backpack I will have to carry, and the heat, and the sand...