The Pennsylvania Railroad Company was chartered by the Pennsylvania legislature on April 13, 1846 to build a private railroad line from Harrisburg to Pittsburgh. Construction began in 1847 and the first section opened from Harrisburg west to Lewistown on September 1, 1849 (including the original Rockville Bridge across the Susquehanna River). Further extensions opened to McVeytown on December 24, Mount Union on April 1, 1850, Huntingdon on June 10, and Duncansville (west of Hollidaysburg) on September 16, 1850, taking it to a connection with the Allegheny Portage Railroad on the east side of the Allegheny Ridge. On the other side of the ridge, the main line opened from Conemaugh (on the Portage Railroad east of Johnstown) west to Lockport on August 25, 1851. On December 10, 1851, sections opened from Lockport west to Beatty (west of Latrobe) and from Pittsburgh east to Brinton, with a temporary stagecoach transfer between via the Southern Turnpike and a short turnpike branch built to Beatty. Part of that gap was filled on July 15, 1852, from Brinton east to Radebaugh, and on November 29 the full line was completed, forming the first all-rail route between Philadelphia and Pittsburgh, though still using seven of the original ten planes of the Allegheny Portage Railroad.