Founded in 1895, the Delaware County Historical Society is the oldest historical society in Delaware County, Pennsylvania. Its mission is to acquire, preserve and make available documentation of Delaware County history; to provide and support educational programs on the history of Delaware County; and to publish materials relevant to this history. DCHS operates two buildings: Greenbank Farm in Marple and the 1907 Delaware County National Bank building in Chester, the latter of which houses the Society's research library and museum collections. The Society's archival holdings consist of over 47 collections that span over 1,200 linear feet of materials dating from 1716 to the present, although most of the collections date from the 19th and 20th centuries. While many areas of Delaware Country are represented, the City of Chester is especially well-documented. Original manuscripts, which include ledgers, scrapbooks, correspondence, photographs, deeds, ephemera, maps, and other documents, relate to various people, families, organizations, particularly community associations, businesses, and local government. The collections also include vertical files on various local history topics that mostly consist of secondary-source materials such as newspaper clippings, pamphlets and ephemera, research notes, transcripts, indexes, printed materials, copies of church and civil records, death and funeral records, and census and tax records, with some original materials such as oral histories.