The remains of the castle can be visited
Raspenburg Castle

The Raspenburg castle ruin is on a mountain spur on the northeastern outskirts of Rastenberg in Thuringia. Its location on an old trade route over the Finne gave it importance for centuries.
History+
The origins of the Raspenburg date back to shortly after 1085, when Ludwig the Springer acquired the surrounding area through marriage and had castles built there to consolidate his power in the Saale-Unstrut region. The complex served as a residence for Ludowingians such as Heinrich Raspe III and later Heinrich Raspe IV. It was part of a network of station castles that served the administration and defense of the Landgraviate of Thuringia. After the death of Heinrich Raspe IV in the Thuringian-Hessian War of Succession, the Counts of Rabenswalde initially took over the rule, followed by the Wettins from 1288. In the course of conflicts over the Landgraviate, the castle changed hands several times and degenerated into a robber baron's nest.
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: 51.1783, 11.4217