Great Coastal Railway Journeys

Michael Portillo heads to Northern Ireland's spectacular Causeway coast to begin a new journey, which takes him along the north and east coasts through Ulster and Leinster. He begins in Co Derry on the windswept shores of Loch Foyle, where the largest accumulation of coastal sands in Ireland has formed a system of dunes visible from space. He also learns how scientists are monitoring the site and hears how their work has been picked up by fellow scientists in the United States to help research the surface of Mars