John Piper - 1944 - A Ministry of War Transport crane unloading armoured vehicles from US ships at Cardiff Docks during WWII. [000] Cardiff Docks became a immensely important base for US shipping during WWII and many US registered ships were based there and used to transport coal, steam engines, cars, lorries, armoured vehicles, supplies and men to the french ports in support of allied actions against German aggression. Penarth and Fowey were the chosen harbours for the shipment of armaments and explosives.