The remains of the Castle can be visited
Hohenburg Castle

In Homberg an der Efze in the Schwalm-Eder district, Hesse, the Hohenburg castle ruin, also known as Homberg, stands on a basalt cone. This hilltop castle was once a strategically important point on historical trade routes.
History+
The exact construction date of the castle is unknown, but a Rentwich von Hohenburg was mentioned as early as 1162. From around 1190, the complex belonged to the Landgraviate of Thuringia and was first documented in 1246. In the 13th century, it fell to the Landgraviate of Hesse and became the administrative center of the Homburg office. Archbishop Hermann IV of Cologne, brother of the Hessian Landgrave Ludwig II, had the castle rebuilt in 1508. Between 1605 and 1613, Landgrave Moritz reinforced the complex and restored the 150-meter-deep castle well.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Roland Neubert, Halle (Saale)
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: 51.0366, 9.4062