The Abbey Church is positioned in the center of the fortified complex of Abbadia Isola and consists of a three-aisled basilica. The present church was built in place of a previous church which had a structure with three naves divided by pillars ending in an apse and a crypt; The present Church, although heavily altered over time, appears as the result of a single construction phase.
Inside, we can find a fresco with Madonna enthroned with child, Angels and Saints by Taddeo di Bartolo, dating back to the late 14th century;we can also find a beautiful baptismal font of1419 and the fresco of the assumption of the Virgin by Vincenzo Tamagni (1520).
On the high altar we can admire a marvellous painting by Sano di Pietro of 1476 depicting the Madonna and child with Saints Benedict, Cirino, Donato and Justina.
