The team's journey starts in Cardiff marina, takes in the Gower Peninsula and finishes in Britain's smallest city, St David's. Neil Oliver accompanies Babs, the land speed record-breaking car from the 1920s, on its return to Pendine Sands. Mark Horton explores how Swansea's monopoly of the world copper trade sped Nelson towards his victory at the battle of Trafalgar. Miranda Krestovnikoff joins the dolphins who come to the Welsh coast to raise their young.