In a new three-part series historian Michael Scott explores deep underground using the latest laser-scanning technology and Virtual Reality to reveal the historical secrets of three great cities: Cairo, Athens and Istanbul.
　　The Invisible Cities scanning team helps us to see these cities as no human eye ever could; in Cairo Michael explores deep inside and beneath the first pyramid ever built at Saqqara and finds out how it helped inspire the Great Pyramid of Giza; in Athens he reveals the secrets of a temple on the Acropolis and goes underground to see the silver mines that funded the world’s first democracy, and in Istanbul he discovers layer upon layer of history from the Greeks and Romans, to the Ottoman Empire and brings the city’s tumultuous history alive in the Hagia Sophia.