Homepage for the Library of Congress, the de facto national library for the United states; includes links to the catalog, digital collections, and online exhibits.

Homepage of NARA, the national archives for the United States; includes links to the NARA catalog of finding aids and digital materials along with valuable information about starting your research in the archives.

Useful for finding repositories and also for tips on searching for manuscripts; sponsored by the Library of Congress.

Part of the University of California’s California Digital Library (CDL); provides access to archival finding aids from more than 150 repositories in California, also contains digital materials. The Cal State East Bay University Archives is part of the OAC.

“A listing of over 5000 websites describing holdings of manuscripts, archives, rare books, historical photographs, and other primary sources”; resource for finding archives that may contain collections of relevance to your research project." NOTE: "Effective January 1, 2015, the list of Repositories of Primary Sources will no longer be updated or maintained."