My husband and I took one with Odysseys last fall. There were only 22
of us from all over the USA. Our host was most knowledgeable. He secured
excellent guides in each city as well. He took care of all our needs, even
being at the airport to be sure the different ones departed with no problems.
You would have to do an awfully of reading to learn as much as we did. Of
course, when you are on a tour, you are limited to their hours. I think of
tours as giving you a taste of each place. Then you may want to go back to
your favorites on your own another time.