The International Survey of Jewish Monuments provides a searchable database of information on historic Jewish sites in North America, including synagogues, cemeteries and houses.
A collection of 2,800 lantern slides from the Harvard Graduate School of Design, housed by the Library of Congress. Views of cities, specific buildings, parks, estates and gardens.
Christine Madrid discusses and illustrates the visitor centers built in US national parks 1956-1966 as examples of early modern, distinctly American architecture.
The official site provides a searchable database of properties on the Register, information on listing, virtual tours of historic sites, resources for teaching, and order form for its publications.