First of all: Thank you Dirk for that great travel guide through Germany.
For the listeners of these episodes I have an additional idea on how to see Germany (and other European countries): by bicycle.
As Dirk is completely biased with his suggestions, I am as well. Because I already did some of those bicycle tours myself.
If you want to see the Rhine Valley from Bingen to Bonn (the Mittelrheintal) you can actually perfectly do so by bicycle. There’s one of those European cycle routes running right through it: The EuroVelo 15.
https://en.eurovelo.com/ev15
When I did that from Koblenz to Porrentruy in Switzerland it worked perfectly fine for me. When I am doing such vacation I usually do legs of 100 – 120 km (60 – 75 miles) a day. Something that is perfectly possible on an e-bike. An e-bike might seem a bit lazy at first glance, but don’t forget that you need to carry all your belongings along on the ride. For the most part the assistance helps to counter that additional weight.
What do 100 – 120 km a day mean? At about 20 km/h that’s two to three hours cycling before lunch and two to three hours cycling after lunch. While those lunch breaks take about an hour in which I eat three courses and let the battery of the e-bike recharge.
As a tourist, completely new to Germany, you might want to shorten those legs to 60 km a day, so you’ve got more time for sightseeing.
You should check literature on what to carry along on a bicycle tour. For example you should always have the tools to replace a broken bicycle tube, to do basic repair along, with clothes for rainy weather and a first aid kit.
On top of that I have clothes for three to four days along. (Which I wash along the way in self-service laundries. There’s a lot of those in France, for example.