For two days before this year’s Holmenkollen cross-country ski races, Espen Garder took his remote meetings from a heated tent in the forest. Breaks came only for lunch and battery charging at a restaurant up the hill.

Garder, 53, had arrived early to claim a spot, not just for himself but also for the dozen Boy Scouts he leads. They would join him for the weekend, eager to sleep in the subfreezing temperatures along the 5-mile racing loop.

Thousands more fans, no less excitable, would take day trips on Oslo’s metro system to pack Holmenkollen’s ski area for one of the world’s most improbable winter sports festivals, capped by a weekend of cheering, drinking and mania for cross-country skiing, which in Norway is something like a religion.