The remains of the Castle can be visited
Lichtenberg Castle

The Lichtenberg Castle Ruin, also known as "Heinrichsburg," is an archetypal example of a high medieval hilltop castle. Duke Henry the Lion built the site as a stronghold.
History+
The origins of Lichtenberg Castle date back to the early 12th century, with expansion occurring between 1170 and 1180. Duke Henry the Lion used it as a fortress against the Prince-Bishopric of Hildesheim and the Staufer neighbors in Goslar. In 1180, the castle was conquered by Emperor Frederick I (Barbarossa) but returned to Henry the Lion in 1194. After his death in 1195, the castle played a role in the conflicts between the Welfs and Staufers, particularly under Otto IV, who threatened the imperial city of Goslar from here. In 1206, Count Hermann von Wöltingerode captured the castle for the Staufers, but in 1208, it returned to Welf possession.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: https://de.wikipedia.org/wiki/Datei:Lichtenberg_Burg_Gesamt.jpg
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: 52.1215, 10.2882