National heritage areas : hearing before the Subcommittee on National Parks of the Committee on Energy and Natural Resources, United States Senate, One Hundred Eighth Congress, second session, to conduct oversight on national heritage areas, including findings and recommendations of the General Accounting Office, the definition of a national heritage area, the definition of national significance as it relates to national heritage areas, recommendations for establishing national heritage areas as units of the National Park System, recommendations for prioritizing proposed studies and designations, and options for developing a national heritage area program within the National Park Service, March 30, 2004.