The ceiling of Cathedral Basilica of SS Peter and Paulus   – Natural light is admitted through the clerestory windows close to the ceiling. These are of lightly tinted glass and carry simple religious symbols (IHS (Christ), three lilies representing the Trinity, a key (Saint Peter), a cross, a crown of thorns, a sword and scripture (Saint Paul)) as their most prominent decorations. Gold rosettes on a rich blue background adorn the coffered ceiling. Bronze chandeliers, weighing a half ton each, light the nave. (cathedralphila.org)