American FactFinder (AFF) has two tools for creating, viewing, printing, and downloading maps:
The reference map shows you selected geographic boundaries for an area along with orienting features, such as roads. To view a reference map, select the geographic area you want to see. You can customize the map by adding different boundaries or features.
The map always starts with a view of the United States, but you can change that by clicking on the area of the map you want to view in more detail, or by selecting a new geography using the geography link at the top of the Reference Map page.
Click 'Quick tips' for assistance in navigating or customizing your map.
Use thematic maps when you want to see a comparison of statistical data, such as population or median income, displayed in a map format. You can view interesting facts about places by comparing the patterns of shaded areas or colors on the map.
You can change the view of the thematic map by clicking on the area of the map you want to view in more detail, or by selecting a new geography, theme, or data set using the links at the top of the Thematic Map page. You can also change the data values associated with each color for a different view of the same data, and you can add a title to your map.
Click 'Quick tips' for assistance in navigating or customizing your map.
This diagram shows the many geographic types for which data are available from the U.S. Census Bureau.
With connecting lines, the diagram shows the hierarchical relationships between geographic types. For example, a line extends from states to counties because a state is comprised of many counties, and a single county can never cross a state boundary.
If no line joins two geographic types, then an absolute and predictable relationship does not exist between them.
For example, many places are confined to one county. However, some places extend over more than one county, such as New York City. Therefore, an absolute hierarchical relationship does not exist between counties and places, and any tabulation involving both these geographic types may represent only a part of one county or one place.
Notice that many lines radiate from blocks, indicating that most geographic types can be described as a collection of blocks, the smallest geographic unit for which the Census Bureau reports data. However, only two of these lines also describe the path by which a block is uniquely named. That is, the path through the Block Group or through the Tribal Block Group.
In addition to the maps found in American FactFinder, there are other products available to help you build maps.