Cardiff in making iron and later steel, brought to the sea by packhorse from Merthyr Tydfil. This was first achieved by the construction of a long canal from Merthyr (510 feet above sea-level) to the Taff Estuary at Cardiff. Eventually the Taff Vale Railway replaced the canal barges and massive marshalling yards sprang up as new docks were developed in Cardiff – all prompted by the soaring worldwide demand for coal from the South Wales valleys. At its peak, Cardiff's port area, known as Tiger Bay, became the busiest port in the world and – for some time – the world's
Cardiff Bay railway station a Grade II* listed building. The station is within walking distance of the Senedd and the Wales Millennium Centre Passenger services are provided by Transport for Wales. The station is due to close by December 2023, when the new Cardiff Bay station opens. The line to the docks was opened on 9 October 1840 but the station was not mentioned in Bradshaw's railway timetables until December 1844. It was opened as "Cardiff Bute Dock" but the name was changed to "Cardiff Docks" in 1845 by the Taff Vale Railway (engineer: Isambard Kingdom Brunel). The station building was the head office