Even on a tight schedule, Museo dell'Opera del Duomo earns the hours.
Allow 1–1.5 hours.
This is the most underrated stop in Florence: modern, uncrowded, climate-controlled, and holding the original sculptures pulled off the cathedral for protection. The catch: it's already inside the Brunelleschi pass that everyone buys for the dome, yet most people skip it out of fatigue. If you have any interest in sculpture, it's the best-value culture hour in the city.
Holds Ghiberti's original gilded 'Gates of Paradise' (made 1425–1452) plus Michelangelo's Bandini Pietà and Donatello's Magdalene; over 750 works across 720 years of cathedral history. · en.wikipedia.org
The museum reopened on 19 October 2015 after a major two-year restoration and enlargement; it is included in the €30 Brunelleschi Pass. · duomo.firenze.it