>>2618497 (lb)
When Q sez to think Rome, I'm thinking the Vanderbilts aren't the only ones to own a private slaughter pool. The different tiles could be representative of those other pools. A place accessible to the artist in Europe? Rome? Vatican city?
Famous for its walls, but what if there's a tunnel to the outside, ie a nearby convent. So people like Podesta could enter to partake in sacrifices.