Wallenstein Castle, Medieval castle ruin in Knüllwald, Germany.

Wallenstein Castle is a medieval fortress ruin perched on elevated ground in Knüllwald, with preserved stone walls and a standing tower section. The remains reveal the layout of a fortified settlement with clear defensive features that protected this strategic location.

Built probably in the 12th century by Hersfeld Abbey to control its western territory, the castle was held in pledge by Count Albert V of Schauenburg from the early 13th century; he called himself Albert von Wallenstein from 1223. In 1637 Croatian troops of the emperor destroyed it in the Thirty Years' War, and it was never rebuilt.

The name comes from the von Wallenstein family, who called themselves after the castle from 1223, when Albert V. von Schauenburg took it in pledge. Since 2000 the village association Burg Wallenstein e. V. has held annual knight games and a medieval market in the ruins.

The ruins are accessible year-round and reached via marked hiking trails from Knüllwald. The walk to the site gives you a good chance to explore the surroundings and approach the location from different angles.

The round stair tower that survives was fitted with a spiral staircase in modern times and turned into a viewing tower. The castle was bought by the Fritzlar-Homberg district in 1957 and repaired to stop further decay. Since 2000 the village association Burg Wallenstein e. V. has held annual knight games and a medieval market among the walls.