For those with an interest in historical US maps, this site will be of value. The Library of Congress has recently added to its American Memory Collections a small preview set of 19th and early 20th century panoramic maps, also known as birds-eye view maps. These are "nonphotographic representations of cities portrayed as if viewed from above at an oblique angle," and, though not drawn to scale,...
The US Library of Congress American Memory site has recently added this new item to its impressive collection. Railroad Maps, a preview release provided by the Geography and Map Division of LOC, contains a searchable and browseable selection of maps taken from RailroadMaps of the United States, by Andrew M. Modelski.