Several years ago while stationed in Germany the wife and I took a cruise down the Danube. It was a very interesting tour, lots of sightseeing, and lots of beer and wine pushed our way.
As I said, I took the tour because I was there. I liked museums, the arts, and the food, but I have no desire to do it again. If you have never been there, it will be a worth while trip, and there are lots of things to keep you entertained while there, you may even have an opportunity to visit a German gun shop. One thing I advise everyone traveling to a foreign country of, you are a guest in their country, don't expect them to speak English just to please you, don't expect any special favors just because you are American, and your rights as an American are no longer valid while on their soil. There will be a lot of people waiting to rip you off so take only those items you need, protect your money, travel checks, and passport at ALL times. Be careful in crowds, do not let them separate you and your wife even for a moment while on the street, or out in public. And last but not least, be careful how you conduct yourself if you do catch someone getting light fingered with your stuff.
After seven years in Europe, between Germany and Spain, I'll be happy to spend my remaining days in the good ole USA. Course in 24 years of military service I seen Greenland, Viet Nam (twice), Australia, Japan, South Africa, Germany and Spain. The time spent in Germany and Spain afforded the opportunity to travel and see most other countries in Europe and the Mediterranean area.