The remains of the Castle can be visited
Hauneck Castle (Ruin) (Oberstoppel)

The Hauneck ruin is on the Stoppelsberg in Oberstoppel, a district of Haunetal in Hesse. This hilltop castle now offers a wide view over the surrounding landscape.
History+
The origins of Hauneck Castle likely date back to the 14th century, when it was built by the Knights of Haune. Its first documented mention occurred around 1397, when Landgrave Hermann II of Hesse conquered the castle after a conflict and had it repaired. In 1409, the Landgrave officially acquired the complex from Heinrich von Haune, whereupon Hauneck became a Hessian judicial and administrative seat. A second destruction occurred in 1469 during the Hessian Fratricidal War.
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: 50.7515, 9.7011