At the centre of the apse is the Assumption of Mary with Angels and Saints, attributed for years to Domenico Ghirlandaio but which is instead the work of an anonymous Florentine painter from the 1400s, while on the sides are two frescoes by Giusto Rossi depicting the Holy Family and the Madonna and Child with a Young St. John the Baptist.
On the side walls, you can see four altars: the second to the left vaunts a beautiful 15th-century painting with the Santissima Annunziata, or Holy Assumption, that was strongly inspired by the Florentine sanctuary of the same name.
Above the confessionals, built in finely carved walnut, you can see various episodes from the Life of the Virgin Mary, and above, six ovals painted by Vincenzo Pacini in 1747, three on each side, depicting other Vallumbrosan saints.
The organ is also exquisite, richly decorated with moulding and engravings, as is the parapet on the engraved and gilded Rococo choir from the 1700s.
Under the high altar is the body of St. Vincent Martyr, moved here from the San Ciriaco catacombs in 1676. On the floor, several stone hatches indicate the presence of mass graves, two of which are reserved for monks and abbots, respectively.