Will you have a car?
Some ideas for a day trip (going east of Bologna on the A14 (or even better, the SS9, which follows the path of an old Roman road):
The mosaics of Ravenna
The world-class ceramics museum in Faenza
The striking murals painted on the walls of the old town of Dozza
The memorial to Formula One champion Aryton Senna along the F1 track in Imola
(Offbeat): Mussolini's crypt in an old cemetery just outside the small town of Predappio (a few miles south of Forlì) (a small, well-preserved eleventh-century church sits next to the cemetery)