Roman Colosseum Exterior Close-Up Jigsaw Puzzle

Did you know? The Colosseum's outer wall required over 100,000 cubic meters of travertine stone held together by 300 tons of iron clamps — no mortar. A retractable awning called the velarium covered two-thirds of the arena, angled to catch the wind and provide a breeze for up to 80,000 spectators. Source