Route for May trip

This probably won't help you very much since you won't have a car. My wife and I had a car and when we left Venice our plans were to take the Great Dolomite Road in one day and spend the night in Bolzano and see Otzi the iceman. Instead of driving the road in one day we took almost three days and two nights. One night in Canazei and the next at the Alpi di Siusi. The views were stunning and we stopped every few miles it seems for photos. It was one of the highlights of our trip. You could check on a bus tour of the Great Dolomite Rd and see what you could find. If you decide to rent a car you could do so in Bolzano and take the route RS suggests in his guide book and turn your car in at Verona or possibly somewhere close to Venice. The car would allow you so much flexibility for stopping for photo ops, etc. If you want to stop for the night you would not have any problem finding a room in May. Most lifts are closed in May. BTW,the museum in Bolzano containing Otzi is worth a visit.

The Alto Adige has excellent bus service. We stayed in Castelrotto. The bus terminus, into which many lines converge, is close to anything in town. We rode down to Bolzano twice, about 1 hour each way, for 2.50 euros one way. These local buses run very frequently. We also booked a bus tour of the Great Dolomites road at the TI office for, I think, 24 euros pp. It was all day, with many photo op stops and an hour for lunch in Cortina D'Ampezzo. The only drawback was that the narrative was in German. However, if you know this ahead, you might be able to find a good guidebook to read about what you aare seeing.