TILT down, Interior: vaulted ceiling of the Nave, triforium and clerestory windows, main apse with altar. Erected between the 11th and 14th centuries, the basilica preserves the west porch in Romanesque design, giving way to a similarly Romanesque building with three naves and three apses. The church stands where San Vicente and his sisters are believed to have been martyred in 303 AD. Avila is a World Heritage Site of UNESCO.