Greifenstein Castle, located on Bad Blankenburg's local mountain, approx. 25 minutes from the town center, is part of the is one of the oldest feudal castles in Germany. Today the castle, which was known as Blankenburg Castle until the 17th century, consists of a main castle with a palace and tower. It has Several castle courtyards and bastions. The Counts of Schwarzburg-Blankenburg resided here in the 13th and 14th centuries.

The castle's sights include the Open-air performances at the Adlerhof and Falkenhof, which also remind us of the castle's founding legend:

Greif, the favorite falcon of a Schwarzburg count, had flown away. It was not until days later that he was found on a remote mountain, sitting on a block of stone. The lucky count was so taken with this mountain that he had a castle built here, which was to be named „Greifenstein“.