Castel Sant'Angelo

Castel Sant'Angelo is one of Rome's most flexible monuments because it has been emperor's tomb, fortress, papal refuge, and museum. That history is visible in the route: thick defensive walls, ramps, interior rooms, and the terrace that opens toward the Vatican and the river. The best reason to come is the layered view of Rome itself, especially the curve of the Tiber and the approach to St. Peter's. It is a strong late-afternoon stop because the top terrace and the riverfront light are both more appealing then.