We did this excursion on our 'In the Wake of the Vikings' cruise, and I would highly recommend. I know it's possible to book similar excursions with independent providers for less money, but in our case, at least, the van Viking used was only partially filled, we had a terrific guide who gave us in-depth commentary at all the stops, there was plenty of time to walk around and explore at each stop, and at the end, the driver gave us a quick unscheduled tour around the city itself.