Did this route yesterday. The scenery is very nice but the route was not really what I was looking for. Lots of traffic, no really good sweeping corners. Lots of small towns along the way which gets really annoying! Its more of a cruise and take in the scenery route. But pleasant all the same.
Part 2 of The famous German castle road. A really beautiful and quiet route which follows the river Neckar, drives in Bavaria forest and runs through lot of castles. Awesome scenery and not traffic at all. The complete roads goes like this: Heidelberg - B37 - B27 - Heilbronn - B39 - L1035 - L1036 - Langenburg (great castle)- Rothenburg (another one great castle) - B13 - Ansbach - B14 - Nornberg
Note: there are lot smaller castles around the route