Tim Dunn looks inside the former HQ of London Underground, 55 Broadway, which was the capital's first skyscraper. He visits the rural Norfolk station that used to serve the monarch's Sandringham Estate and sees the timber-framed Barmouth Bridge in north Wales.

Tim Dunn visits Swindon's railway village, which became home to Great Western's enormous works and he also explores the dark and secret past of Milan's station.