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
Sand Bay A Pontins holiday camp was opened in Sand Bay in 1947, remaining with the company until 1999. During its peak of popularity it had 300 chalets spread over . After Pontins, the site was owned by the Holybush Hotel group under the name of Sand Bay Holiday Village. With cabaret, tea dances, comedy and music, it remains a popular destination. In 2008, The company has rebranded to Martyn Leisure Breaks and is now known as Sand Bay Leisure Resort. In 2013, Martyn Leisure Breaks entered administration and closed the park. In 2014, it was announced that the site would re-open