Mapping The
Western United States

Topographic Atlas Projected to
Illustrate Explorations and Surveys West
of the 100th Meridian of Longitude.
George M. Wheeler's Map of Colorado
Geography and Map Division

One of the primary objectives of Wheeler's survey was the preparation of a systemic series of topographic, geologic, and land-use maps of the western United States. Displayed here is the topographic map sheet for northern Arizona, depicting the rugged terrain of the Grand Canyon of the Colorado River. Although Wheeler's mapping program was never completed, it did provide the basis for the founding of the U.S. Geographic Survey.