Ptolemy, the Greek geographer who did map work in Alexandria in about 150 A.D., is generally considered the father of cartography. His work, "Geographia," was the first and most popular cartographic publication to be printed from movable type in the 15th and early 16th centuries and remained the principal work on the subject until the time of Columbus. Although amazingly accurate for the time, the work had Asia extending much too far east.

The earliest atlases in the Library are associated with Ptolemy, including 47 of the 56 known copies of "Geographia" dating from 1475 to 1883. These join the ranks of the more than five million maps and 500 globes, 72,000 atlases, 6,000 reference works and numerous plastic relief models and cartographic materials in other formats, including electronic, in the Geography and Map Division.

The division celebrated a landmark in map digitization with the mounting of the 10,000th map on its Web site. The November 2006 issue of the Library of Congress Information Bulletin features an article recognizing the accomplishment, which is Samuel de Champlain's 1607 chart on vellum of the North American coast from Nova Scotia to Massachusetts.