Baltimore

Fells Point.   Explore this area in Baltimore using cascading clickable maps.  Nice photos and short histories for a variety of locations.  [ccr]
http://www.baltimoremd.com/fellstour/index2.html

Urban geology in downtown Baltimore.  From the Maryland Geological Survey, this is a map-based guided tour showing detailed photos and descriptions of stone used for major buildings.  [ccr]   
http://www.mgs.md.gov/esic/features/walking/