Colditz Castle: Built strategically on a cliff in 11th-century Saxony, Colditz Castle had been used as a military outpost, a zoo and a mental hospital before it became a prison for political prisoners under the Nazis. Click through the gallery for more of Germany's most intriguing castles:
Heidelberg Palace: Constructed of pink-brown sandstone that turns the color of bubblegum at sunset, Heidelberg Palace is surrounded by woods and terraced for views overlooking Heidelberg and the Neckar Valley.
Wartburg Castle: Surrounded by forests in Eisenach, Wartburg Castle was home for a time to Martin Luther. He translated the New Testament into German here.