Pennsylvania Railroad Company. Predecessor and subsidiary companies (Lines East).

Records of 97 predecessor and subsidiary companies lying east of Pittsburgh and Erie. Hard copy records are available for those companies lying south of Philadelphia.

After 1850, the Pennsylvania Railroad Company grew by creating wholly-owned subsidiaries to build branch lines, and by absorbing previously independent railroad systems. Over the years, the number of subsidiaries was reduced by an ongoing process of reorganization and merger.

The major systems absorbed by the PRR were: The Northern Central Railway (1861), the Baltimore and Potomac Railroad Company (1868), the United Railroad & Canal Companies of New Jersey (1871), the Philadelphia, Wilmington & Baltimore Railroad Company (1881), the Western New York & Pennsylvania Railway Company (1900), and the Long Island Railroad Company (1900).