We stopped off at Ravenna on our way from Padua to Arezzo.
We parked in Largo Giustiniana, a manned car park located close to Basilica di San Vitale.
The main reason for visiting Ravenna is the amazing mosiacs.
Here is all the information you need: http://www.ravennamosaici.it/?lang=en
Make sure you pay the extra 2 euro to include a visit to Mausoleum of Galla Placidia.
The map lists the properties and shows the walking route: http://www.ravennamosaici.it/?page_id=9&lang=en
If you park in Largo Giustiniana the ticket office is close to the Basilica di San Vitale.
You can take photos inside all the properties except the Museo Arcivescovile.