Even on a tight schedule, Trevi Fountain earns the hours.
Allow 15–30 min.
Genuinely spectacular and free — a wall of sea-gods and crashing water wedged into a tiny square — but the honest tension is sound versus crowd. At 7am or after midnight you can hear the water and almost have it; any other time the roar competes with a wall of selfie sticks. The trick most miss: step up to the church terrace at the top of the square for a head-on view over the scrum.