The Archaeological Conservancy is a 501(c)3 non-profit organization that acquires and preserves archaeological sites in the United States. Whereas nearly every other nation protects all archaeological sites within its borders as part of its national patrimony, in the United States archaeological resources on private land are the private property of the landowner. As a result, archaeological sites in the United States are subject to destruction by urban development and sprawl, mechanized agricultural and land-leveling, and commercial looting to fuel the antiquities trade. By the 1970s the extent of archaeological site loss was increasing recognized as a crisis for the scientific study of the nation's past. - Source: Wikipedia