Built on the site of a Christian basilica which had been occupied previously by a temple dating from Roman times. The construction began in 1163 and the facade was finished in 1200. The two towers were not finished until 1245. After that they started working on the intierior and the church could be said to be finished in 1345. With the ravages of time and damages caused by men and numerous tragic wars, the church's original apperance changed over the centuries, espicially during the revolution. In 1793 in ran the risk of being demolished. In 1802 Naploleon crowned himself Emperor when he took the crown away from Pope Pius VII and then crowned his wife.