The birthplace of Catherine was converted into a sanctuary in 1465 and is now a group of superimposed chapels. On the lower floor you can visit the Oratorio della Camera, inside the saint's former bedchamber. On the upper floor, the oratory to the left has fine 17C majolica tiling; the one to the right houses a painted crucifix (13C), before which St Catherine is said to have received the stigmata in Pisa.