We booked a short Norwegian Fjords tour on the Arcadia. The Arcadia is adults only but the epithet applies only to age and not to any "special" activities.
Prior to embarkation we were informed that the first port of call would be Stavanger, not Bergen, and then the last port of call, for half a day, would be Bergen. As the cruise guides and publicity make out that Stavanger is not so great for shopping or sights (rubbish by the way) and wait for Bergen, half a day is a bit of a cheat really.
In fact Stavanger is quite pleasant and well worth a walk around.