Construction of the Louisa Railroad began in October 1836, reaching the Louisa courthouse by 1839, and by 1840 had reached Gordonsville. The railroad had been planned by its original charter to build across the Blue Ridge Mountains to Harrisonburg, but in 1839, the Commonwealth requested a survey to be conducted to determine a feasible route to Staunton by way of Charlottesville. Ultimately, this route, which passed over the mountains at Rockfish Gap, was chosen as a better alternative than the original plan to cross at Swift Run Gap to the north. In 1847, the charter was modified by the Assembly to provide for the railroad's construction to the eastern base of the Blue Ridge, and in 1849, the Blue Ridge Railroad was chartered to cross the mountains at Rockfish Gap to Waynesboro. Claudius Crozet was appointed Chief Engineer of the Blue Ridge Railroad, and under his leadership and direction, the railroad began construction over the Blue Ridge using a series of four tunnels. Meanwhile, the Louisa Railroad had reached the Rivanna River near Charlottesville by 1850 and by 1852 had reached Mechums River, near the eastern end of the Blue Ridge Railroad.