Incorporated on 21st July 1856
A double-gauge line connecting the Taff Vale Railway with a point on the River Ely, to be converted to a tidal harbour. In 1857 the name was changed to the Penarth Harbour, Dock and Railway, and new capital was authorised. The line was leased to the Taff Vale Railway and passed to the Great Western in 1922.

Capital £130,000 in shares of £100 each, loans of £43,000. New capital for improvements in 1857; £192,000 in £100 shares and £21,000 in loans.