Discover two of romes lesser known treasures castel santangelo and ponte santangelo on this 3 hour tour with an expert guide enter the castle and learn how it served as a mausoleum for roman emperor hadrian before becoming a papal fortress tour the lavish apartments and museum see the remnants of hadrians tomb and admire the city views from the rooftop plus wander across the ponte santangelo a roman marble bridge lined with exquisite statues numbers are limited to 20 people on th