1/16/1904 — Sectional view of Pennsylvania Railroad Tunnel Now Under Construction Beneath the Hudson River History of transportation in Ohio — maps of railroads in Ohio including the Pennsylvania Railroad Harvard College: 20th century great American business leaders — Martin W. Clement Rensselaer Polytechnic Institute: Alumni hall of fame: Alexander J. Cassatt Ray Hiebert papers at the University of Maryland Libraries are a collection of official press releases from the first 50 years of the Pennsylvania Railroad 1846 establishments in Pennsylvania 1968 disestablishments in Pennsylvania Conrail Defunct companies based in Pennsylvania Defunct Delaware railroads Defunct Illinois railroads Defunct Indiana railroads Defunct Kentucky railroads Defunct Maryland railroads Defunct Michigan railroads Defunct Missouri railroads Defunct New Jersey railroads Defunct New York (state) railroads Defunct Ohio railroads Defunct Pennsylvania railroads Defunct Virginia railroads Defunct Washington, D.C., railroads Defunct West Virginia railroads Former Class I railroads in the United States Predecessors of Conrail Railway companies disestablished in 1968 Railway companies established in 1846 Railroads in the Chicago metropolitan area Standard gauge railways in the United States