The history of the world as told through one hundred of the objects that time has left behind. The objects are from the British Museum and tell the story of humanity over the past 2 million years. They are chosen by the museum's director, Neil MacGregor. This week he is exploring the world along and beyond the Silk Road in the 7th century AD at a time when the teachings of the prophet Muhammad were transforming the Middle East forever. Today he looks at how the Syrian capital Damascus was rapidly becoming the centre of a new Islamic empire. He tells the story through two gold coins that perfectly capture the moment - with contributions from the historian Hugh Kennedy and the anthropologist Madawi Al-Rasheed. Producer: Rebecca Stratford.