Good overview of the town with glimpses of the salient points of interest. Land and water tour. Bring a jacket if seated in the back by the open windows!
Beautiful scenery with an interesting historical narrative from the tour guides.
For those who love old houses with great architecture and colorful histories, the castle tour is a must. Note that there is a lot of walking and climbing of a steep street, so one should be reasonably fit. The city part of the tour pointed out the places of interest, but we didn't have a whole lot of time to explore since we were in port for only a few hours.