Burg Konradsheim, Late medieval water castle in Konradsheim, Erftstadt, Germany

Burg Konradsheim is a late medieval water castle in Erftstadt, North Rhine-Westphalia. The main house is a two-storey brick building with stepped gables, a round tower with a conical slate roof, and a rectangular wing with dormers and chimneys. A red sandstone bay window on three corbels stands on the west side.

The castle was built around 1337 by Arnold von Buschfeld, a knight who later placed it under the authority of Archbishop Walram of Jülich. A renovation in the 16th century gave the building its Renaissance features, which have shaped its appearance ever since.

The street name Qualenberg near the castle comes from a misreading of the old field name Quadenberg, which recalls the knight Hermann Quad, who held property in Konradsheim in the 14th century. The family von Konradsheim later used income from its estates here to help fund Cologne's reopened priest seminary.

Burg Konradsheim stands on the Frenzenstraße (L 162) at the northern edge of Konradsheim, about two kilometres north of Lechenich. The site is a private property, so visits are limited to viewing the brick buildings and the moat area from outside. The former outer bailey survives only as the bailiff's two-storey brick house with a stepped gable.

The gatehouse's missing north wing was rebuilt on its old footprint in 1963/64, and a valuable door frame from the former Lürken Castle was set into the northern gate wing. The north-corner tower, like the west tower, had been demolished; it was raised by two storeys at the same time, while the west corner tower remains unfinished up to parapet height.