Dating back to the 18th century, its sacristy is the former chapel of Saint Martin. It was once the burial place for the children and the poor of polignano; a trapdoor in the sacristy floor is the entrance to the ancient underground cemetery.

The concave/convex façade with a portal is divided in two orders. On the portal architrave there are skulls, bones and a hour-glass in bas-relief, the characteristic elements of the churches used as  burial places.