Privately funded by the Marquess of Londonderry. Seven mile railway to link his Penhawpit to his new harbour at Seaham. Though its official opening date is unknown the first coal shipping was done on the 25th July 1831. THe line was extended North to Sunderland on 8th February 1853. This was opened officially on 3rd August 1854 but it was in use by the January of that year. The railway (not dock) was taken over by the NEW in 1900 for the sum of £400000.