I had to look it up
https://en.wikipedia.org/wiki/Castle_Road
From the list, I visited:
Heidelberg Castle - Didn't like it but that's because I visited much nicer places on the same trip, like the one just below. Otherwise, it's pleasant place. I went to see Nazi Amphitheater and Ancient Monastery Ruins which is on the other side of the river. My photos:
https://goo.gl/photos/d5tcCLPXjK7WWkax8
Rothenburg ob der Tauber - lovely place. There are car parks outside of town walls. It's worth walking on the City Walls, hiking up The Town Hall Tower to see the town from the top. You can also buy some souvenirs in Christmas Shop

My photos:
https://goo.gl/photos/uzFw3Sk5aP95z8zb7
Double Bridge outside of town is nice place to take a picture with your car
Nuremberg Castle - Was ok, but nothing great, seen better. I stopped in Nuremberg for one night.
Bamberg- lovely town, spent there whole day when doing weekend trip in C63 to burn petrol ;-) I took boat trip, but I think half time was a bit wasted as I wasn't interested in harbour.
This is one of the most known views:
Visited Prague number of times. Don't forget to buy vignette before crossing the border.