The brick-built Gothic cathedral was constructed between the 13C and 15C on the site of an earlier building twice destroyed by fire. The crypt contains the shrine of St Knud and that of his brother Benedikt. Behind the altar is the magnificent triptych by Claus Berg (1520), comprising more than 300 carved figures. The church also contains some wrought-iron grilles by Caspar Fincke (Christian IV's official craftsman), a 17C bronze font and an 18C pulpit.