Bertholdsburg Castle (Schloss Bertholdsburg) is a historic 13th-century residential castle in Schleusingen, Thuringia, Germany, renowned as the former seat of the Counts of Henneberg-Schleusingen. It houses the Natural History Museum, featuring geology, mineral, and dinosaur exhibits, and is known for its Renaissance architecture and scenic castle gardens. Built around 1230. Features a 33-meter high main tower from the original medieval structure and a four-wing Renaissance layout from the 15th-16th centuries.