My favourite spot in Hagia Sophia, is the tomb of the blind Doge of Venice, Dandalo.

It was he who led the Fourth Crusade, which in turn led to the sack of Constantinople (as it was called then) in 1204 over a dispute about money   He was the first man over the walls, and oversaw (in a manner of speaking) the destruction of the most fabulous city in history. His tomb is a small modest affair on the first floor of the Empress's private chapel.