Library of Congress: Maps
The Geography and Map Division (G & M) has custody of the largest and most comprehensive cartographic collection in the world with collections numbering over 5.5 million maps, 80,000 atlases, 6,000 reference works, over 500 globes and globe gores, 3,000 raised relief models, and a large number of cartographic materials in other formats, including over 19,000 CDs/DVDs. The online Map Collections represents only a small fraction that have been converted to digital form. An example map.
See also Online Collections Listed by Theme
Old Maps Online
OldMapsOnline developed out of a love of history and heritage of old maps. The project began as a collaboration between Klokan Technologies GmbH, Switzerland and The Great Britain Historical GIS Project based at the University of Portsmouth, UK thanks to funding from JISC. Since January 2013 is the project improved and maintained by volunteers and the team of Klokan Technologies GmbH in their free time.
David Rumsey Map Collection
Probably the largest free online digital collection of historical topographic maps and images. Although the main focus for the collection is rare 18th and 19th Century North and South American maps it also includes a variety of other historical cartographic materials covering the rest of the world. It is presented through a range of different viewers.
British Library Maps Collections
The British Library's map collection spans the world.
World Digital Library
The WDL makes it possible to discover, study, and enjoy cultural treasures and significant historical documents on one site, in a variety of ways. Content on the WDL includes books, manuscripts, maps, newspapers, journals, prints and photographs, sound recordings, and films. WDL items can be browsed by place, time, topic, type of item, language, and contributing institution. The search feature can be used to search all of the metadata and descriptions and the full text of printed books on the site.
The World Factbook provides information on the history, people, government, economy, geography, communications, transportation, military, and transnational issues for 267 world entities. Our Reference tab includes: maps of the major world regions, as well as Flags of the World, a Physical Map of the World, a Political Map of the World, a World Oceans map, and a Standard Time Zones of the World map.