A late Gothic church (1326-1475), Siena's Franciscan barn was badly damaged in a 1655 fire and used as a military barracks for a long time before being reconstructed in the 1880s. On the inside of the entrance wall you can see what happens to frescoes that are left out under the elements. Remounted here are heavily deteriorated works that once graced tabernacles at the Porta Romana (on the left, painted by Sassetta and Sano di Pietro) and the Porta Pispini (on the right, by Sodoma). In the second chapel to the right of the altar is a tomb with a schiacciato effigy carved by Urbano da Cortona (1462-87); the chapel to its left has a 14th-century Madonna and Child by St. Catherine's friend Andrea Vanni. The first chapel left of the altar contains a detached Crucifixion by Pietro Lorenzetti, whose brother Ambrogio did the excellent frescoes, now in poor condition, in the third chapel down. What's left of these early 1330s works, Ambrogio's first fresco attempt, depict the Martyrdom of Franciscan Missionaries at Ceuta and St. Louis d'Anjou Taking Leave of Pope Boniface VIII, where Lorenzetti makes the viewer part of the onlooking papal court.