Byzantium

"Not since the world was made was there ever seen or won so great a treasure, or so noble or so rich, nor in the time of Alexander, nor in the time of Charlemagne, nor before, nor after, nor do I think myself that in the forty richest cities of the world had there been so much wealth as was found in Constantinople. For the Greeks say that two-thirds of the wealth of the world is in Constantinople and the other third is scattered throughout the world."

Robert de Clari
French crusader who witnessed the pillage of Constantinople by the Crusaders in 1207.