The remains of the castle can be visited
Lauenburg Castle

The Lauenburg castle ruin is a two-part hilltop castle in the Harz mountains, near the village of Stecklenberg.
History+
Lauenburg was built as an imperial castle in the third quarter of the 11th century under Henry IV and was first documented in 1164. Its construction, which spanned about ten years, served to protect Quedlinburg and military roads. In 1180, the castle fell to Frederick I Barbarossa during armed conflicts. Later, it was temporarily used by robber knights before being destroyed in the 14th century. After 1740, the complex was sold for demolition.
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: 51.7268, 11.0803