Washington

Historic Edmonds walk.  Tour historic sites, with then and now images, from a clickable map. [ccr]
http://www.historicedmonds.org/historic/historicwalk/walk.html

Ozette Research Program.  A clearinghouse for information from Lake Ozette region research projects provide by Andy Bach of Huxley College of Western Washington University.  [tdh]
http://www.ac.wwu.edu/~andybach/Ozette/index.html

Whatcom County Critical Areas and Shorelines.  A map-based tour of a variety of environments surrounding Bellingham, with good physical geographical explanations of each.  Created by the Whatcom County Planning and Development Services.   [ccr]
 http://www.co.whatcom.wa.us/pds/shorelines_critical_areas/vtour_map.jsp

Historic Downtown Issaquah.  Map-based historical tour, with a few photos.   [ccr]
http://issaquahhistory.org/sites/walkingtour.htm

Historic Olympia.  Presented by the City of Olympia, here is a map-based site showing 32 of that city's historic buildings and other sites.  Includes photos and text covering history and architecture.  [ccr]
http://www.trpc.org/external/programs/historic+preservation/olyhistoric/olymap.htm

Digital Atlases, Searchable Digital Archives, and Other Sites Useful for Exploring Places:

Washington Atlas of Panoramic Aerial Images.   A collection of medium-scale images across the state, including many that are rather spectacular.  Created by William A. Bowen through the auspices of the California Geographical Survey at CSU Northridge.  [ccr] 
http://130.166.124.2/wa_panorama_atlas/index.html