Rhine River in January ??

If you take the train to Rüdesheim, you can catch a ship going down the Rhine. Check the KD schedule though, as I believe there is only 1 ship per day in the winter.

Let me know if you need more suggestions for Frankfurt.

Thanks, Ms Jo. Hope to see you if you get to a Sacramento meeting.

The winter (frigid) cruise only happens once per day at 10:00 am and only then if enough folks sign up in advance for that day.

Much better IMO to grab a warm window seat on the train from R'heim north to Braubach - which takes you right along the river bank through the most scenic part and drops you at the home of Marksburg Castle, which is open 11-4 daily in winter. If you don't wish to tour the castle, or even if you do, you can ride the train into Koblenz and change trains there for a return ride along the opposite side of the river so as to enjoy the view from different perspectives. You may wish to stop over for an hour in Boppard, Oberwesel, and/or Bacharach, attractive towns which mostly hibernate in winter but still have some wonderful old-world buildings, old town wall remnants and towers you can check out. The best scenery is done with by the time you reach Bingen. Then you head back to Frankfurt via Mainz, a handsome university town of some size that is quite alive even in winter and also worth a stop.

Mainz, old town zone

I kind of like riding the ship in the winter. Get a seat in the stern along the back window, turn your chair around and you get a wonderful view of both sides of the river. One problem with the train is that if it is foggy out, you will see absolutely nothing and this has happened to me on more than one occasion. It won't be much better in the ship, but the experience is nicer. The towns along the Rhine are unbelievably dead in the winter. About the only ones with some business are going to be Rüdesheim, and possibly Bacharach, Boppard or Eltville. One suggestion I have is instead of going to a castle, consider going to Eberbach Monastery which is close to Eltville. Close to a 1000 years old, it is magnificent in all of its' Romanesque glory.

Marksburg is tough to get to in the winter. Having climbed the path going up there myself in snow, ice and mud, my experience is that it is very difficult and scary to say the least.

Thanks to all for the advice. This part of the trip was a specific suggestion from DH who has fond memories of the 8 years he spent in Germany -- possibly his recollection of winter has faded over the last 30 years in California.