Fischenich Castle, Castle ruin in Fischenich, Hürth, Germany

Fischenich Castle is the ruin of a hillside castle on the Vorgebirge slope in Hürth-Fischenich, between Genner, Augustiner and Jakobstraße. Originally an oval round structure with four towers, it is now almost entirely enclosed by rows of houses. It is considered the oldest surviving castle complex among the fortifications between Cologne and Bonn.

The castle was built by the Lords of Fischenich, who served the Cologne archbishop as ministeriales in the 12th and 13th centuries. In 1309, Knight Contze von Vischenich enfeoffed it to Archbishop Heinrich as an open house. It stayed with the von Fischenich family for five generations until Jutta von Fischenich married Dietrich von Zweiffel in 1455. The Burghaus was demolished at an unknown date, possibly after French damage in 1794–1797.

The name Fischenich comes from the knightly family von Fischenich, ministeriales of the Cologne archbishop in the 12th and 13th centuries. The castle remained a fief of the Electorate of Cologne even though the village belonged to the Duchy of Jülich, and its holders sat in the Cologne Landtag. A visitor can still see the oval ground plan of the former four-towered castle, now enclosed by rows of houses.

The site is accessible via marked pathways and has parking available nearby. Walking around the ruins is straightforward on ground that ranges from flat to gently sloped.

The ruin is considered the oldest surviving castle complex among the many fortifications on the Vorgebirge ridge between Cologne and Bonn, and one of the most important witnesses of High Medieval castle building in the Rhineland. Its former oval layout with four towers is now almost entirely enclosed by rows of houses.