The Consolidated Rail Corporation (Conrail) was incorporated in October 1974. It was formed under the auspices of the United States Railway Association, a quasi-public agency established for the purpose of solving the problems of bankrupt railroads in the Northeast and Midwest. The Conrail photograph collection consists of a large number of images from its company files, but the majority of the material comes from its predecessor companies: Pennsylvania Railroad and Penn Central Transportation Company. These items are predominanatly composed of photographs, negatives, transparencies, lantern slides, and films.

The Jackson and Sharp Company, a manufacturer of railroad passenger cars, was incorporated in Delaware on February 24, 1869, as the successor to the partnership of Jackson & Sharp. This collection contains copy photographic prints of the company plant.

The Reading Company, chartered in 1871 as the Excelsior Enterprise Company, became the holding company for the system of railroads, canals, and coal mines assembled by its predecessor, Philadelphia & Reading Railroad Company, between 1833 and 1896. The records are a fragmentary group from the Philadelphia & Reading Railroad Company; its successor, the Philadelphia & Reading Railway Company; and its subsidiary, the Philadelphia & Reading Coal & Iron Company. They are primarily registers of employees and wage rates for employees in the Reading, Pennsylvania, repair shops of all three companies.