Anyone visiting Venice in the last ten years will have suffered the unsettling experience of seeing what appears to be a small ugly modern city moving slowly above the rooftops of the city. The scale is so preposterous and the aesthetics are so ludicrous, compared to the ancient city, that it’s easy to believe that the looming behemoth is a hallucination. It’s not. In fact, you will have just seen one of hundreds of mega-cruise ships that annually pass dangerously close to the Piazza San Marco in order to supply its privileged passengers with their iconic view of la Serenissima. To be fair, most of those passengers probably have no idea of the damage being done so that they may enjoy this fleeting experience. If they did, cruise liners would surely not be swarming into Venice's historic byways like vast white locusts.