Gingerbread Castle, Hamburg NJ Unfortunately in need of repair, but I just love roadside attractions. I loved it as a child, and still love it as an adult. Enough that Katie and I have trespassed there many times to take pictures.
Flak Towers of Austria and Germany - The Nazis built eight of these massive above-ground, anti-aircraft gun blockhouse towers in Hamburg, Berlin and Vienna. Good luck trying to demolish these babies. Repurposing them is rather difficult as well.
Trendelburg Castle, Steinweg 34388 Trendelburg, Germany One of Germany's best-preserved castles, located in the Wester Mountains near Kassel. Chartered in Trendelburg held a strategic position, dominating trade roads from Frankfurt to Kassel and Hamburg.