Maps make your family history come alive. It is impossible to understand the lives of ancestors without consulting maps. There are many online that are helpful and can be downloaded or purchased.
The Library of Congress offers maps collections. Two of my favorites are the Civil War Maps and the Railroad Maps. Use the Civil War collection to enhance your ancestor's military information. The railroad collection will enable you to visualize the growth of the system and in so doing understand your ancestor's migrations.
One of my favorite web sites is Color Landform Atlas of the United States. You can view maps by selecting from the options of shaded relief map, black and white map, county map, satellite image, 1895 map or PostScript map. The shaded relief map is not only colorful, but allows you to see the mountains or hills, along with rivers and valleys.
Another extensive collection of maps on Internet is the David Rumsey Map Collection. Here you will find over 20,000 maps and images of the 18th and 19th centuries.
Determine exactly where your ancestor lived in 1895 by using the 1895 US Atlas. Here you will find population statistics, an index of towns and cities and map of the state and county as it appeared in 1895. The 1914 County Maps by State provides similar information only for 1914.
Various states have maps online that are historical and helpful. Historical Maps Online from the University of Illinois at Urbana-Champaign is a great place to look for topographic maps of Illinois, but they also have maps of other locales. Virginia County and State Maps is great for that state.
An extensive collection of links to maps is Historical County Lines (USA). You can locate a county of interest online at County Boundary Map. It's easy to link counties together and see the towns and cities.
The New York Times hosts an Interactive Map Showing Immigration Data Since 1880. You can select a foreign-born group to see how they settled across the United States.
Search for maps online by using Google or checking out map categories on Cyndi's List.