of the Foundation in 1987 was provided by the brothers Franz Joseph van der Grinten and Hans van der Grinten who were looking for a site for their private collection of modern art. On 24 May 1997 the completely renovated buildings and the gardens were reopened. Building history The former fortified farm was in 1345 to 1355 redesigned by Roland von Hagedorn into a classical gothic castle with a square floor plan. In addition to three round towers it had on the north corner of a more powerful, fourth round tower, which served as a dungeon. From the interior courtyard the third tower was accessible and provided all sorts of comforts, such as a well, toilet, light niches and a fireplace. The western side of the castle was at that time, a great hall, the other sides consisted of walls with battlements. South of the main castle was a bailey, the castle gate through which the main castle was reached. In the 15th century in the courtyard of the main castle building new wings were built and a decorated chapel was added in the east tower. Alexander Baron von Spaen had the medieval fortifications expanded and rebuilt in 1662 as a baroque castle styled like the buildings from the capital city of Kleve by Pieter Post. Since only a year before the renovation work at Castle Ringberg was completed you can still today see architectural parallels between the two castles. The basement rooms received new, concave sides and the floor heights were changed. Also the windows of the main castle windows were arranged symmetrically and the approaching roads were moved so that they leads axially towards the main house. Under Johann Nikolaus von Steengracht from 1854 to 1862 a remodeling of the exterior was done in the Gothic Revival style. The Baroque interior was maintained largely untouched during the work under the Cologne Cathedral architect Ernst Friedrich Zwirner. The castle walls were covered with red brick and the three corner towers were fitted with battlements and pointed windows. The keep was set up with a historicist pointed roof. The gateway also experienced a reorganization and was made accessible via a newly built stone bridge. In the course of this work, the fore-castle was rebuilt on the foundation of its predecessor. In addition, the builder replanted the parks in the "mixed style" of that time. In this can be found in