The ruins of Ebersburg Castle are located on a porphyry cone on the southern edge of the Harz Mountains, north of the village of Herrmannsacker, above the Sägemühle inn on Breitensteiner Straße. The castle ruins are over 800 years old and enchant visitors with their romantic charm. The ruins are dominated by the mighty castle tower. With its height of over 18 m and impressive wall thickness of 4.75 m, which is still preserved today, it conveys an impression of strength, power and duration.

The castle was built from 1180-91 at the behest of Landgrave Hermann I of Thuringia, certainly not least to show his power to the outside world and to assert his presence internally. It was the northernmost fortification of the Thuringian Empire and is probably the only castle ruin in Germany today that has been preserved as a purely Romanesque complex.