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
Leckwith, Cardiff Road, Sloper Road, Clive Street, Ferry Road, and Cardiff Bay. But as the Cardiff Leckwith has no official status the area has no formal boundaries and the name is sometimes used for locations outside the historic parish. The name "Leckwith" is an anglicisation of the Welsh "Lecwydd" (see Leckwith for a fuller explanation). The old stone triple-arched Leckwith Bridge crosses the river Ely to the west. It is Grade II* listed and dates from before 1536. Leckwith, Cardiff Leckwith () is an area in the west of Cardiff that includes parts of the communities of Canton and Grangetown. Leckwith includes