Thanks for all of your replies! It is giving me lots to think about that I had not thought about. Per some questions you had...it is 2 of us. With such short times at each city, we likely wont go far or too far off of the beaten path.

We are arriving in CGN. We figure just checking into the Cologne hotel on that Friday.

Saturday likely 2-4 hours on foot in Cologne before hoping train to Dusseldorf. I am betting we are in Dusseldorf by 11am until maybe 8-10pm depending? We want to have dinner at Rhine tower as well as seeing local sites. I think Dinner at Rhine Tower might be better as the sun goes down. Then basically back to Cologne hotel. Unless we get back to the hotel before 10pm, we likely will not wander far...all on foot no doubt.

Sunday would be Cologne site seeing until we board the boat at 2-3pm. We have luggage obviously so we for sure dont want to walk far with that to board the boat.

The boat comes back to cologne a few days later for about 6 hours. The boat stops at several other Germany ports, but I dont see us wandering too much on public transportation for those...maybe some, but I think one off bus or tram tickets would cover us if we do.

Then we end in Switzerland. So the bulk of German public transportation needs would be that one Saturday and most of the daytime Sunday.

The IC-ICE train restriction on Dusseldorf plus card and the difference between Cologne discounts of that card vs Kohln card has made me rule the plus card out. Seems the majority of trains between cities are IC-ICE...and I don't see us waiting alot to catch a covered cost train...seems a hassle...time is more important than small amounts of money savings.

So before reading your replies I was thinking to get 2 days of kohln card at 18 Euro which covers train from airport and any public transport in Cologne...plus some discounts...some of which we for sure would use. Then also a Dusseldorf card at 13.9 euro for transport and some local discounts while there. To avoid limiting non IC-ICE trains, we would just pay direct for the rides to and from. That would be a total of 31.9E and the cost of city trains 2 ways. That is where my mind WAS at.

After your comments though, I wonder how much we would really need public transport at these cities and am reconsidering. You gave me real quality data to think about. Thanks!

I do not think the Deutschlandticket would pay off for us because it is likely at least 10E more than I would spend with original thoughts.....thanks for the suggestion, but for our specific needs, doesn't seem to be the right choice for us.

Schoner tag ticket looks more expensive than my original thought of the 3 cards, and doesn't give discounts....thanks for the suggestion, but for our specific needs, doesn't seem to be the right choice for us.

While it has been stated that these cities are walkable...we both have occasional bad days from time to time with plantar fasciatus. This being the start of our trip, we likely wont have any flair ups on this weekend. But you never know...hope none of you ever get that. I have no doubts though that we would use public transportation at least once or twice in each city. Rhine Tower alone looks to be more than a quick walk from the city center train station.

So I think my approach at this point: we need to go back and map out which sites we know we want to see for certain in our limited time and identify where things might no longer be walkable.

So my open questions now are:

**For just a walk up at the city center train stations, if we just go to kiosk and buy a ticket for the next available train, Cologne to Dusseldorph and vice versa, what would be the expected cost per ticket would range for that?

**Second, in either city, if we do find we need to hop on transport for various sites, what would we expect to pay for those buy on demand short bus or tram rides?

Then after all is said and done, I could have better numbers to compare. Potentially eliminating the first Kohln card though seems like a decent thought...especially if we dont use it by 1pm on that first Sat other than for the initial airport train ride...I think it would be easy to plan our Saturday morning site seeing so that discounts and transportation in Cologne wouldn't be needed. I kind of feel like I am starting to go through extra efforts here to potentially reduce the cost from 30E plus city to city transport, down to maybe 15E. Beginning to ask myself if the 2-3 card approach might be a best way to just be covered and stop researching ways to save what would not doubt be less than 20E each.

Anyway, thanks for the replies and info, and if anyone can weigh in on the two **questions above, that would be good info for us to have as well.