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This entry was originally written by Dwight A. Radford in Red Book: American State, County, and Town Sources.
The United States Geological Survey (see page 5) publishes catalogs of topographical maps covering the state of Wyoming: “Wyoming Catalog of Topographic and other Published Maps” and “Wyoming Index to Topographic and other Map Coverage.” The catalogs list over-the-counter dealers of U.S. geological maps in Wyoming.
The U.S. Geological Survey has designated certain libraries in Wyoming as map depositories. These include Casper College and Natrona County Public Library in Casper; Wyoming State Library in Cheyenne; Campbell County Public Library in Gillette; University of Wyoming, Coe Library and Geology Library in Laramie; Central Wyoming College in Riverton; Western Wyoming Community College in Rock Springs; and Sheridan College in Sheridan.
The Wyoming State Archives has online historic, detailed maps on its website at http://wyshs.org/maps.htm.