I just read your journal and it looks like a really nice route. Plus, there are bike ferries?!?! It's worth going just for that ! ! !

I just found out a friend in Frankfurt (Klaus, if you're reading my most recent journal posting) will be helping out/riding with us on this trip, so I think I'm going to do the Moselle route, but after reading all of the wonderful comments about the Danube I will definitely be riding it at some point. Thanks for the input Rich! (and everyone else!)

Mark, a bit late in the day, I guess, but since the Danube has been properly celebrated, here's my 2 cents' worth:  In 2012, from mid-Sept to early Oct., I made my first long-ish tour, up the Rhine and down the Danube.  Started in Nijmegen in Holland, rode south along the Rhine to Mainz; took the train  SE from there to Ulm; and from there, rode east to Vienna.  

Lovely time of year, splendid riding on the radwegen, almost all flat, with hills available if you wanted a side trip; A-grade cafés; reminders of history both inspiring  (I managed a nod to Marcus Aurelius in Tulln, just W of Vienna -- see photo below) and ghastly; and as always, enjoyable chance conversations and the kindness of strangers.  

I have a journal of sorts -- the one I posted to crazyguy got lost in the shuffle when I left -- but wd be happy to review it and share it with you if you like.  Pls let me know if so, but don't feel obliged.  You can reach me at  johncsaxby(at)rogers(dot)com

Cheers,  John