Denver is up and running after a major blizzard grounded flights and stranded passengers last week. To understand what it takes to put an international air hub into the deep freeze, check out this bird’s-eye image of the snowbound facilities.

That’s right, in the week between Christmas and New Year’s Eve, 65 million americans will be in the air or on the road. That’s almost double the number who traveled over Thanksgiving weekend, and an increase of one million from last year.