For their churches and private palaces, popes and princes have stripped the Colosseum of its precious marble, travertine, and metal.
The Colosseum was stripped of it's materials, most by royalty.
mnli hypothesis: The Colosseum was stripped of it's materials, most by royalty. premise: For their churches and private palaces, popes and princes have stripped the Colosseum of its precious marble, travertine, and metal.