The Alaska Highway's route through northwestern Canada and Alaska is located in the discontinuous permafrost zone, where the soil is frozen solid in some places and boggy in others. Frozen earth, swampland, and changing temperatures forced road construction crews to improvise solutions to problems introduced by geology and weather.

Cold-weather engineering challenges persist today. The U.S. Army Corps of Engineers operates the Cold Regions Research and Engineering Laboratory, with projects offices at Fort Wainwright and Fort Richardson, Alaska, to expand knowledge about the world's coldest regions.

In this feature, discover how Army engineers negotiated with nature to blaze a trail through the wilderness.