Not far from the Castello Estense in the centre of the town. The façade of this large basilica is quite grand, a mixture of Romanesque and Gothic. The interior is not lit very well so is rather dim and some features and sculptures are difficult to see clearly. It is only open at certain times of day so you will need to check with someone in the know, or else take a chance(I had quite a long wait in the afternoon until the doors opened). Nearby is the Cathedral’s museum which contains art and exhibits and is quite interesting(There is an admission charge to the latter).