Old Court House Civil War Museum

Winchester, Virginia, served as a prison/hospital during the Civil War.

Old Dominion University Library

Virginia.

Old Forge Library

New York.

Old Jail Museum & Library

Hiddenite, North Carolina. Home to the Alexander County Ancestry Association, Inc.'s Genealogical Research Library.

Old Rugged Cross Historical Museum

Reed City, Michigan. Houses the archives of the Reed City Area Genealogical Society.

Old Time Corner - Essex Centre History Records & Stories

A research library focusing on artifacts and material in Essex County, Ontario, Canada. Growing online database of photographs of cemetery headstones in southern Ontario.

Old Town Public Library

Maine.

Oldham County Clerk's Office

Kentucky.

Oldham County Public Library

Buckner, Kentucky.

Oldham Local Studies & Archives

Lancashire, England.

Olean Public Library

New York.

Olive Free Library Association

West Shokan, New York.

Olivia Public Library

Minnesota.

Olivia Raney Local History Library

General information about the ORL with links to a description of research materials, programs, projects, speakers, and the Wake County Genealogical Society.

Omaha Public Library

Nebraska.

Omro Public Library

Omro, Wisconsin.

Onarga Community Public Library District

Onarga, Illinois.

Oneida Public Library

New York.

Online Archive of California

A component of the California Digital Library, the OAC includes a single, searchable database of finding aids to primary sources and their digital facsimiles. Primary sources include letters, diaries, manuscripts, legal and financial records, photographs and other pictorial items, maps, architectural and engineering records, artwork, scientific logbooks, electronic records, sound recordings, oral histories artifacts and ephemera.

Online Archive of New Mexico

Integrated source for searching and navigating finding aids to archival collections.