In this episode Michael Wood traces India in the days of the Roman Empire. In Kerala the spice trade opened India to the world, whilst gold and silk bazaars in the ancient city of Madurai were a delight for visiting Greek traders. From the deserts of Turkmenistan Michael travels down the Khyber Pass to Pakistan to discover a forgotten Indian Empire that opened up the Silk Road and at Peshawar built a lost Wonder of the World.

• Michael Wood