The remains of the Castle can be visited
Bilstein Castle (Ruin) (Albungen)

West of Albungen in the Werra-Meissner district of northern Hesse, the Bilstein Ruin, once the seat of a Thuringian noble family, stands. Of the former hilltop castle, only a few wall remnants and traces of a cellar and well remain today.
History+
The origins of Bilstein Castle date back a long time, possibly to an already destroyed predecessor. The family, later known as the Counts of Bilstein, can be traced back to Wigger I in the 10th century. After its destruction around 1100, the castle was rebuilt in 1120 by Count Rugger II. From about 1140/1145, he and his descendants adopted the name "von Bilstein". Around 1283, the castle was owned by Heinrich von Treffurt, who also called himself Heinrich von Bilstein. In 1291, Landgrave Albrecht of Thuringia besieged and conquered the castle, accusing the Bilsteins of highway robbery.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 51.2273, 9.9647