Castel Sant'Angelo

This imposing cylindrical fortress began as Emperor Hadrian's grand tomb in 139 AD and transformed over centuries into a papal stronghold with hidden passageways and Renaissance frescoes. Climbing to the rooftop terrace rewards you with sweeping views of Rome's domes and the Tiber River winding through the city. The castle's blend of ancient Roman engineering and medieval-Renaissance additions tells a fascinating story of how Rome continually reinvented its most iconic structures.