It is very difficult to get to or from Volterra without driving. There is no train service, and bus services are sparse.
I think you'd have to bus and train to Florence and then you can train on to Verona. It isn't especially easy to get to Florence. This article tells you how to get from Florence to Volterra and has links to timetables, so presumably you will be able to use it to work out how to do it in reverse:
Noted - thanks.
Thanks heaps guys, we are taking the train from rome to stay in Siena and then catching a bus from Siena to Volterra for a couple days. I'd herd that getting there maybe a bit harder than other places but i will check out the links you have sent thanks
I'm pretty sure that you have to make a pretty tight change at Colle di Val d'Elsa to get from Siena to Volterra. Check out the busfox website for timetables.