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This entry was originally written by Dwight A. Radford for Red Book: American State, County, and Town Sources.
Maps are essential in conducting on-site research, locating towns and cemeteries, and plotting mining claims. Several maps are available for Idaho that are helpful in conducting on-site or historical research.
The United States Geological Survey maps are available for Idaho. Major libraries in Idaho have been designated by the U.S. Geological Survey as map depository libraries. They include Boise State University in Boise, Albertsons Library www.library.boisestate.edu; University of Idaho in Moscow www.lib.uidaho.edu; and Idaho State University in Pocatello www.isu.edu.
Ralph N. Preston’s Maps of Early Idaho (Corvallis, Ore.: Western Guide Publishers, 1972) is an excellent collection of early Idaho maps beginning with the 1804 Lewis and Clark trail map to a present-day map of the state. The various maps detailing the history of Idaho are valuable for genealogical research as they show overland stage routes, old military roads, Indian battlegrounds, old forts, old mining areas, and early towns. Another set of historical maps that has been published by the Idaho State Historical Society and annotated by Meryl W. Wells is An Atlas of Idaho Territory, 1863–1890 (Boise, Idaho: Idaho State Historical Society, 1978).