There are several castles in Europe called "Ehrenfels." This one is located in Switzerland and is known as "Ehrenfels Castle (Grisons)."
The castle began as a tower fortess (bergfried) built in the early 13th Century. In the early 14th Century, the castle was expanded to add the ring wall and residential buildings.
The castle was abandoned by 1600. In the early 20th Century the ruins were restored and converted into a youth hostel. The castle today is probably not historically accurate.
My reconstruction of Ehrenfels Castle attempts to represent the castle as it may have originally looked. My castle is 20 x 25 inches (64 x 80 studs) and is 26 inches high.
For more photos of my reconstruction of Ehrenfels Castle
For photos of the real Ehrenfels Castle and other source