The remains of the castle can be visited
Metilstein Castle

The Metilstein castle ruin, a protected archaeological monument, is located on the 375-meter-high local mountain of Eisenach in Thuringia.
History+
The origins of Metilstein Castle possibly date back to before 1200, potentially serving as a residence for a collateral line of the Treffurt knights. Massive stone structures support this assumption. During the Thuringian-Hessian War of Succession (1247-1263), the castle became part of a siege ring around the Wartburg, erected by citizens of Eisenach and Hessian and Brunswick troops. In January 1261, Landgrave Heinrich the Illustrious stormed the enemy positions from the Wartburg, including Metilstein, and destroyed them. Although the complex was abandoned, it was partially rebuilt in 1306 by rebellious Eisenachers during the Wettin House War, to be used again against the Wartburg.
Source: Wikipedia · Licence: CC BY-SA 4.0
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: 50.9705, 10.3066