Consecrated in 1075 with a columned portico in front, the cathedral stands on a pretty square, the old Roman forum which has preserved its old flagstones. The campanile with small columns is from the Romanesque-Gothic transition period. Inside, the 13C pulpit and paschal candelabrum are fine works by the Cosmati (a corporation of marble masons specialising in assembling fragments of multicoloured marble and incrusting pieces of enamel on the small columns and friezes of cloisters).