The Geography and Map Division of the Library of Congress provides cartographic and geographic information for all parts of the world to the Congress, Federal agencies, state and local governments, the scholarly community, and to the general public. It is the largest and most comprehensive map library in the world, numbering nearly 6 million cartographic items. In addition to maps, which make up the bulk of the collection, the Division holds thousands of atlases, geospatial datasets, and reference works; numerous globes and three-dimensional plastic relief models; and a large number of cartographic materials in other formats. New items are acquired yearly through government deposits, transfers of superseded maps from federal libraries, copyright deposits, domestic and international exchanges, purchases, and gifts. The oldest collection item dates back to the fourteenth century and continues with coverage of cartographic items produced through the present, representing over 180 countries. Most of our collections are described in the Library of Congress catalog.

Among the earliest original maps in the collections are several manuscript portolan charts and atlases from the fourteenth through seventeenth centuries drawn on vellum by Italian, Portuguese, and Spanish cartographers. The excellent collection of atlases dates from an 1482 printed edition of Claudius Ptolemy's Geography and includes representative volumes of all significant publishers of atlases for the last five centuries. The atlases cover individual continents, countries, cities, and other geographic regions, as well as the world ranging in scope from general to topical.

Of particular interest to genealogists and local historians is a large collection of U.S. county and state maps and atlases published in the nineteenth and early twentieth centuries. Atlases published during the past four or five decades and covering national, regional, state, and provincial resources form another noteworthy reference group. Among the numerous county maps and city and town plans are some 700,000 large-scale Sanborn fire insurance maps, in bound and loose sheet volumes, covering about 12,000 American cities and towns. This collection constitutes an unrivaled cartographic and historic record of America's urban settlement and growth over more than a century.

The division has an excellent collection of manuscript and printed maps of colonial America, the Revolutionary War, the War of 1812, the Civil War, and the wars of the twentieth century. Supplementing these historical records are photo-reproductions of manuscript maps from various American and European archives. The Geography and Map Division maintains more than one hundred individual special collections that have been acquired through gifts, government transfers, and purchases or assembled by division specialists according to common themes. In addition, the Vault collection includes some three thousand manuscript and rare printed maps that have been filed together for their intrinsic, artistic, or historical significance. With few exceptions, these collections are stored in a specially designed vault equipped with temperature and humidity controls.

Ongoing collection development focuses on broadening and enhancing worldwide geographic and thematic coverage; filling identified gaps in existing collections and map series and upgrading the condition and quality; documenting the work of distinguished cartographers and map publishers, particularly American; documenting and illustrating historical events; illustrating the purely aesthetic value of cartographic products; illustrating the technical process of map making, including the variety of printing techniques; documenting and illustrating developments in thematic cartography; documenting non-Western and non-European cartographic traditions; and supporting the collections and reference resource requirements of other areas of the Library.

The Geography and Map Division is interested in enhancing its holdings and would like to learn about the availability of both modern as well as historical cartographic and geographic items and collections. Gifts to the Library from individuals, corporations, and other private sources have greatly enhanced the resources of the Library and are always welcome. For further information about the Geography and Map Division's acquisition program please contact Ask a Librarian.