These bacterial cells were discovered in a tunnel dug by the Army Corps of Engineers in the 1960s in order to allow scientists to study the permafrost in preparation for the construction of the Trans-Alaska Pipeline System.
Three species of bacteria, Carnobacterium pleistocenium, as well as Chryseobacterium greenlandensis and Herminiimonas glaciei, have reportedly been revived after surviving for thousands of years frozen in ice.