The Darlington Collection is extensive collection of rare documents, maps, and other historical material focusing on early American history, particularly that of Western Pennsylvania. The original material is housed by the Archives Services Center (ASC) of the library of the University of Pittsburgh with digitized material available at the Darlington Digital Library. The collection was inherited by Darlington's daughters Mary O'Hara Darlington and Edith Darlington. The donation of the collection was first given to the University of Pittsburgh in 1918. The rest of the collection was donated in 1925.