African-American Maps and Photographs
Maps of the Underground Railroad and photo collections of notable African-Americans.

Civil War Maps
The Civil War Map collection of the Library of Congress Geography and Map Division consists of reconnaissance, sketch, coastal, and theater-of-war maps which depict troop activities and fortifications during the Civil War.

Historical Maps of the United States
The Perry-Castañeda Library Map Collection from the University of Texas at Austin provides maps on early inhabitants, exploration and settlement, U.S. territorial growth, and military history.

United States Maps
Information on how to obtain a variety of maps from the US Geological Survey.

USDA Forest Service
A collection of forest visitor and wilderness maps, regional and state guides, forest land distribution, and more.

World Atlas
Maps and geography of the world, from About.com guide Matt Rosenberg. 

World Maps
Information on how to obtain world maps from the US Geological Survey. Includes political, topographic, seismic, and other maps.