Rhine River Cruises from Cologne?

I will be in Cologne next month. My friend lives in Berlin, but has a house also in Cologne and offered me to stay there for some time. Actually, I think he is just afraid because burglars visited that house several months ago and he just dont like to leave it unattended for more than a month or two. So, what about Rhine River cruise from Cologne?

I dont know what would Cologne be without the Rhine. The entire old town can be seen from the river. There are also many interesting landmarks and buildings to see on each bank. Please, take photo camera with you, the surrounding scenery is very nice and you will really enjoy in those two and a half, almost three hours of the tour. You will even have a waiter with a quick service also, to complete the feeling.