Complex sentence: Charlottesville became a significant junction of the two railroads, with two railroad stations in operation, one on the C&O line and the Union Station just west of the C&O station at the junction between the C&O and Southern railroads.
Split into simpler sentences: Charlottesville became a significant junction of the two railroads, with two railroad stations in operation. One was on the C&O line and the second, the Union Station, was just west of the C&O station at the junction between the C&O and Southern railroads.