The University of Alabama has a collection of historical and contemporary maps on its site. Not surprisingly, many of the maps are of the U. S. south but there is quite a number of maps of other areas as well. Of special interest may be the “Topographical and drainage map of New Orleans” created by T. S. Hardee in 1878. Maps can be viewed as zoomable, pannable jpgs or as Mr SID files (although I couldn’t get the Mr SID plug-in to function).