Cairo, March 2017 - construction workers make a spectacular discovery beneath metres of rubble. At the bottom of a deep pit, buried in mud and debris, lies an enormous crowned stone head. Nearby the torso and plinth. These are the remains of a colossal quartzite statue, 9 metres high and weighing several tons. It’s an archaeological sensation, a clear indication that this was once the heart of an ancient, legendary metropolis - Heliopolis.