In existence since 1931, this nonprofit institution located on Croton Avenue east of Sun Valley Nursery is rich in historical artifacts and information regarding Ossining and its role in New York State. Collections in the museum include daguerreotypes, the first kind of photographs, of Ossining, oral-history tapes, information on Sing Sing Prison, slides and films of old Ossining, maps, genealogy files and newspapers dating to 1818. Old Indian collections are on the first floor of the museum.
The museum has a library of old books on Ossining and a military exhibit. There is a thrift shop whose proceeds go to defraying the cost of maintaining the museum which is entirely run by volunteers.