The David Rumsey Historical Map Collection has over 11,000 maps online. The collection focuses on rare 18th and 19th century North and South America maps and other cartographic materials.

A history of the relation of geology during the first 110 years of the U.S. Geological Survey to the development of public-land, Federal-science, and mapping policies and the development of mineral resources in the United States

using USGS maps to teach about Lewis & Clark