Tamra Reynolds slumps on a faded pink loveseat in a community center in Carmacks, in Canada’s northern Yukon, and stares steadily into space.

The area around her is a bustling checkpoint for what many view as the world’s toughest dogsled race—a spot where mushers like Reynolds who are trying to navigate a 1,000-mile race through the brutal cold can grab a hot meal and a nap, and check in with race veterinarians. And, in many cases, contemplate whether they and their dogs can go on.

Parka-clad race officials and checkpoint volunteers come and go, and local reporters and photographers hunch over their MacBooks at the rows of long tables that fill the room. But Reynolds's corner is a little pocket of calm.

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