With the 1871 decision to build Philadelphia City Hall, the 1876 opening of merchant John Wanamaker's department store to the east, and the 1881 opening of the PRR station to the west, the center of Philadelphia's business district rapidly moved to Broad & Market Streets.
Roberts's first major accomplishment as PRR president was the 1881 purchase of a majority stake in the Philadelphia, Wilmington & Baltimore Railroad, which froze the rival Baltimore & Ohio Railroad out of a direct Philadelphia-Washington, D.C. route that had previously rented trackage rights to both railroads.