We spent 2 days on our own in Amsterdam after the cruise. It's a very lively, multi cultural city with some fun neighborhoods. The Van Gogh Museum and Rijksmuseum are worth visiting if you like art and early furnishings.
Koln is a very modern, large city compared to others we visited. The cathedral was very nice and worth visiting. There is a large, pedestrian shopping area.
Koln is a very large, modern city. The cathedral is worth visiting. There is a large pedestrian shopping area right near the dock.
Our favorite stop on the cruise, Strasbourg is a very nice and clean with a charming old town area. This is the seat of the EU Parliament, with many nice neighborhoods.