We are staying in Koln for 5 days and are interested in taking a Rhine River Cruise. Does anyone have any recommendations on cruises and "must see's"? Thanks.
Try looking at these two websites to see if they have anything that might interest you as far as the boat rides, etc.
http://www.k-d.com/englisch/schiffstouren/feuerwerksfahrten.html
5 days in Cologne?? The Rhine further to the south is much more interesting/attractive than the Cologne portion. Consider 2 days in Cologne and 3 in the Middle Rhine region (between Koblenz and Bingen.) That's where the cruising is best, the castles are many, and the towns (like Bacharach) are full of cobblestones, old town walls and fortifications, and half-timbered buildings.
K-D cruises hit pretty much every little town in this region. Must see: Marksburg Castle in Braubach:
Rheinfels castle in St. Goar and Burg Eltz to the west are must sees.
If you're going in late summer, there is the nighttime Rhine in Flames cruises. We're booked on the 4th of July and I can't wait. The one we're going on starts in Rudesheim, goes to St. Goar and back. The towns along the Rhine shoot off fireworks over the boats going up and down the river and there are fests in the towns.
One problem I found is that all the rooms nearby were booked and we had to go about a half hour away from Rudeshiem to find a room. I should've looked sooner.