Convento di San Marco, also visited as Museo di San Marco, is one of Florence's most atmospheric Renaissance stops, where Fra Angelico's frescoed cells, Michelozzo's cloisters, and rooms tied to Girolamo Savonarola still feel intimate and calm. Just north of the Duomo core, it gives you a quieter art encounter without leaving central Florence.
For most visitors, a prebooked entry ticket with audio guide is the easiest first buy, because it keeps your morning flexible and still gives you solid context inside the cells and cloisters.