The most compelling of all Brescia's religious monuments is the 11th-century Duomo Vecchio, a rare example of a circular-plan Romanesque basilica, built over a 6th-century church. The inside is surmounted by a dome borne by eight sturdy vaults resting on thick pillars.
Interesting features include fragmentary floor mosaics (perhaps from a thermal bath that might have stood here in the 1st century BC) and the elaborate 14th-century sarcophagus of Bishop Berado Maggi (which lies right at the entrance).