The Philadelphia and Columbia Railroad was one of America's first railroads.  It was part of Pennsylvania's Main Line of Public Works, a railroad-canal system that stretched across the state from Philadelphia to Pittsburgh.  The railroad between Philadelphia and Columbia was initially surveyed in 1827, but problems with topography on the eastern end of the line resulted in a re-survey in 1828.   After the 1828 survey was complete, Chief Engineer John Wilson submitted to state officials a detailed report for each of the 83 mile segments including estimated construction costs.  The chart below shows the costs per mile segment starting at Mile 1 on the western end of the line at Columbia, PA and ending at mile 83 at Broad and Vine Streets in Philadelphia.   Costs certainly changed and were much different than these estimates when the whole line opened in 1834, but it does give a good visualization of the disparity along the line, especially for those areas where bridges needed to be built.