Verdict first: choose Centro Storico for first-time visitors who want attractions on the doorstep; choose Monti for a more local, creative vibe at a lower price. Centro Storico puts the Pantheon, Piazza Navona, Campo de' Fiori and the Trevi Fountain within walking distance, but accommodation and dining are pricier and crowded. Monti sits about a 10-minute walk from the Colosseum, Roman Forum and Santa Maria Maggiore, and is full of independent boutiques, vintage shops and wine bars; rooms are cheaper and the feel is more residential. It is also near Termini station and two metro lines. With only 1–2 days, Centro Storico is more convenient; with 3+ days, Monti rewards deeper exploration.