That's one heck of a fortification! I'd love to walk the walls as a student of physical security. Sure, our homes are not literal castles, but they can benefit from some of the security concepts used by them.
Thanks for sharing these pictures and your story to go along with them!
I'll have to try the Radler drink idea. Do they use any particular type of beer, or does it work well with any type?
Usually they take the Pilsener Beer to mix it with lemonade for a radler. I think this is because Pilsener itself has a more or less bitter taste so the whole thing won't get too sweet. Make sure you take lemonade with very natural ingredients or you get a weird artificial taste. In northwest Germany they call the same thing Alsterwasser (like the water of the Hamburg river Alster). If you are in Bavaria you can order a Russ (a Russion). Then it is made of Hefeweizen (Weißbier) and Lemonade.