Altes Schloss, Baden-Baden

Built in the 11th century, destroyed by fire in the 15th century, the Alte Schloss was in the interim the seat of the Margraves of Baden, who maintained military power in the region.
Not much of the structure remains, but the engineering achievement of building at such a high elevation is still impressive. A few of the Gothic touches are still intact, too, hinting at what must have been quite a lovely building despite its military purpose.
After this castle was destroyed, a new castle was built at a much lower elevation, and much closer to the town. Interestingly, the New Castle is owned by the Mubarak family and is being renovated as a hotel. I wonder if they'll get to keep it once they've been put on trial and their assets scrutinized by the Egyptian courts...