Walk ruins of government buildings, temples, and the imperial palace area overlooking the Forum to understand Rome's civic heart; adjacent to Colosseum with combined ticket.
Enter the world's largest church to view Bernini's baldachin and Michelangelo's Pietà; basilica open from early morning to evening (check seasonal times).
Explore the castle museum and terrace for panoramic views, then walk along the Tiber toward Piazza Navona; castle open typically 9:00–19:30 (verify hours).
Visit the best-preserved ancient Roman building with its oculus and grand dome—open typically 9:00–19:00, short visit recommended earlier to avoid crowds.
Stroll the atmospheric ghetto, taste local fried artichokes (carciofi alla giudia), and learn the area's layered history; shops and bakeries open late morning.