By far the corpus of the division's cartographic coverage of the Caucasus appears on maps. While neither complete nor definitive, coverage of the Caucasus is substantial. It is at various magnitudes or scales, and includes maps of the entire region, nations and states, regions within and across states, and cities, each of which may include various categories of subjects. There are two major categories of maps: single maps, which can be either cataloged or uncataloged, and set maps, which by and large are cataloged and may be accompanied by a graphic index or list of contents.
Single maps are those depicting all coverage on a single sheet, but may also include one map on two or more sheets. Theoretically, coverage can be at any scale. Single maps in the Geography and Map Division are filed as either cataloged and uncataloged.
Cataloged single maps are searchable on the Library of Congress online catalog when limits are set by location to "Geography & Map". The LC call number is the map's filing location within the Geography and Map Division.
Uncataloged single maps are filed by a system devised in the late nineteenth century with the founding of the Map Division, and has remained in place, even after the implementation of formal cataloging. Consequently, many maps of the Caucasus acquired prior to 1969 are located in the uncataloged, or "Title," collection. Those are filed by location and thereunder by date and further thereunder by subject, scale, and creator. As an example, a road map of the nation of Armenia dated 1950 could be filed as follows: Armenia -- Roads -- 1950 -- scale 1:1,000,000 -- Michelin
Researchers wanting to examine uncataloged maps must request them from reference staff.
Set maps, or map series, constitute two or more maps of a specific location. Although differences abound, set maps usually are produced at a uniform scale, within a uniform time frame, in a uniform style, and by the same creator or its successor institutions. Depending on their scale of coverage, they can comprise anywhere from two to several hundred thousand maps. Coverage in many large to medium scale sets of maps is indicated by a graphic paper index, and sometimes a list of sheets, which can be filed either by LC call number in cabinets adjacent to the reading room or with the sets themselves. Many sets do not have graphic indexes or lists, and may require a sheet-by-sheet search to identify a specific location. Most sets of maps are cataloged, and can be searched via the Library of Congress Online Catalog, with the search limited by location to "Geography & Map". Because many sets are not cataloged and/or are not described by either graphic indexes or lists, patrons must request assistance from reference staff if attempting to identify and use these materials.