Permafrost Tunnel


The Permafrost Tunnel near Fox, Alaska was excavated in 1963-1969. It is owned by U.S. Army Cold Regions Research and Engineering Laboratory (CRREL). The tunnel penetrates 360′ into the hillside, with a 500′ of total length including the side tunnel and several side rooms. The tunnel cuts through a silt unit formed with syngenetic permafrost with numerous ice features including ice wedges, segregation ice, and thermokarst-cave ice. Since its construction, over 70 technical papers have been based on research conducted within the tunnel and the surrounding property. These topics include placer mining, civil engineering on permafrost, geocryology, geology, paleontology, paleoclimatology, biology including life in extreme environments, and Mars studies. While the existing tunnel still has plenty of research potential, there are limitations due to the original tunnel design and the aging of the 48-year old tunnel walls. To increase permafrost research opportunities, CRREL began planning the tunnel’s expansion in 2009.

To take a virtual tour of the original permafrost tunnel, go here.

CRREL’s Permafrost Tunnel Website