The book is actually volume 2 of the "Rheinisches Land" Collection. I do not have the first volume and am not aware of it's subject matter. This volume was prepared by Dr. Walther Ottendorff-Simrock and does a good job of detailing most (if not all) of the numerous castles along the Rhein River in Germany, between the cities of Mainz and Cologne (Koln). There are a lot of castles through this stretch and I have seen many of them from boat as well as car as we drove along this fantastically scenic part of the world. I've been in about 6 of them but there is so much history surrounding this area that I was happy to dive back into it via this book. I will say that it did serve the purpose but I was a little disappointed in the format of the book. There are lots of great photographs of the castles but generally only of the exteriors. This works for the castles that are mostly ruins but the others often have fantastic interiors which would be of interest. The author presented the history of each castle, what its primary purpose was (defense, river toll collecting, etc.) and added in some info for tourists such as if the castle is open to the public or a private residence, operating hours, etc. The second problem I encountered was that most of the castle descriptions were many pages away from their photos. That required lots of paging back and forth in order to see what I was reading about. I didn't see a need for that; it's not as if all the pictures were collected together in plates. Pretty much each page had a photo on it as well as description...just not matching. I had to count on the "picture on page xx" instructions and when we're talking about 45-50 castles, that's a lot of paging back and forth.
But still, it really brought me back to that time and place, both the times when the castles were active as well as back to the time I lived nearby. Fond memories indeed.