Burg Schlanstedt, Medieval castle in Huy, Germany.

Burg Schlanstedt is a castle complex in Huy, consisting of a medieval core with a trapezoidal ground plan and upper storeys partly built in half-timbering. Its oldest surviving element is a round Romanesque bergfried from the 11th century, 25 metres high, 8 metres in diameter and with walls 2.8 metres thick. A gate tower ruin measuring 9 by 9 metres and a 24-metre-deep courtyard well also remain.

The castle was built in the 11th century by the lords of Schlanstedt to guard the crossing over the Große Bruch, and was first mentioned in 1267. In the early 14th century the Diocese of Halberstadt bought it for 600 Brunswick marks from the von Regenstein family under Bishop Count Albrecht von Wernigerode, who had the round castle rebuilt as a manorial estate. Between 1610 and 1620 the core castle was rebuilt again, producing the Renaissance palace that survives.

The name comes from the village of Schlanstedt, whose lords built the fortress in the 11th century to guard the crossing of the Große Bruch. From 1836 to 1946 the castle was leased to the Rimpau family, known seed breeders; Wilhelm Rimpau is named in 1888. After 1945 refugee flats were set up inside. Visits are not currently possible because ceiling sections are at risk of collapse.

The castle is not open for visits; the building must be renovated and parts of the ceilings are at risk of collapse. The 25-metre Romanesque bergfried with its viewing platform, the remains of the gate tower, the 24-metre well in the courtyard and the dungeon can therefore not be accessed. The site lies at Burg 1 on the southwestern edge of Schlanstedt.

Hidden within the castle courtyard lies a well that plunges more than 24 meters deep, a feature rediscovered in 1994. This forgotten structure reveals how crucial access to water was for those living within the fortress walls.