The Benedictines had the church built in the XIII century, but it underwent radical changes later in the XVI century, owing to the restoration work planned by Giorgio Vasari. Anyway, it is still possible to notice some elements of the original construction, i.e. the “before” window of the facade. Its octagonal bell tower dates back to 1650. The church has got three naves, an arched ceiling, four spans, the presbytery and a rectangular apse.
Entering the church and walking along its right aisle, we can see three altars: on the first one there is a painting by Antonio Lappoli depicting the Visit of the Magdalen to S. Elisabeth; on the second a noteworthy wooden Crucifix, carved by Baccio da Montelupo (1504-10); on the third altar a Madonna with Child and Saints by Bernardino Santini. Further on we find a Crucifix (1319’?) by Segna di Bonaventura. Then, a stone portaI giving access to the sacristy, with a carved wooden door of the XVI century.
On the altar to the right of the high one we can sec a painting by T.Torri which depicts the Mystical Wedding of S. Caterina. The apse preserves paintings by Vasari (on the right) and by T. Torri (on the left). The wooden high altar was built by Vasari (1560-64): at its centre a painting (again by Vasari) portraying Jesus making Peter and Andrew Apostles and at its sides S. Paul (right) and S. Donato (left). To the right of the altar S.Francesco and S. Anton Abbot; to its left Lazzaro and S. Mary Magdalen; higher up two round paintings portraying Chastity and Charity. Above the presbytery there is the false cupola painted on cloth by the Jesuit Andrea Pozzo (placed there in 1702): a perspective view of it offers a suggestive optical illusion.
Along the left aisle, in front of the entrance of the sacristy, there is a XVI century stone altar with a painting of the XVII century. Walking forward towards the exit we can see three other altars with paintings respectively of ‘700 and ‘600.
However, the most important work in the Badia is the noteworthy fresco by Bartolomeo della Gatta. situated to the right of the entrance door. It depicts S. Lorenzo (1476). The cloister by Giuliano da Maiano is also worth seeing: it is situated in the former Benedictine monastery of the Saints Flora and Lucilla, accessible from the Badia square n. 2.