The remains of the Castle can be visited
Questenberg Castle

North of the village of Questenberg in the Mansfeld-Südharz district in Saxony-Anhalt, the Questenberg castle ruin, a medieval feudal castle, is situated. The keep, parts of the curtain wall, two cellars, and a wall of the palas remain today, freely accessible.
History+
The hilltop castle was probably built between 1200 and 1250 by the Counts of Beichlingen and entrusted to a knightly family for defense, which named itself after the castle. From 1305, ownership passed to the Counts of Hohnstein. The castle was first mentioned in a document in 1349 as “hus zcuo Questinberg”. In the same year, Knight Heinrich von me Rade and his brothers received Questenberg and seven surrounding villages as a fief. The Counts of Hohnstein sold the property in 1383 to Landgrave Balthasar of Thuringia. Under the Thuringian landgraves, the castle subsequently served as a pledge object. Thus, from 1424 to 1430, it was pledged to Dietrich von Witzleben and his son Friedrich.
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: 51.4955, 11.1184