The Theme field is used to assign a broad, general subject heading to each map. This will allow for the grouping of types of maps, and will enable easy browsing of the digitized materials. For this field we are using the controlled-vocabulary terms borrowed from the Map Collections on the Library of Congress's American Memory project: http://memory.loc.gov/ammem/gmdhtml/. For the North Carolina Maps project, the term "County Maps" has been added.
- Cities and Towns
- Conservation and Environment
- County Maps
- Cultural Landscapes
- Discovery and Exploration
- General Maps
- Military Battles and Campaigns
- Transportation and Communication.