The Colosseum: A Jewel in Rome's Crown (2021)

Spanning two thousand years of history, this magnificent monument, the Roman Colosseum, is an emblem of the power of a bygone empire. With more than seven million visitors a year, its massive structure and awesome architecture testify to the genius of ancient Roman building techniques, earning it a place not only among UNESCO's World Heritage sites but as one of the new seven wonders of the world.