The Castle can be visited
Favorite Castle

Favorite Palace in Rastatt-Förch, Baden-Württemberg, is an example of Baroque architecture and is considered Germany's oldest porcelain palace. It is the only one of its kind to have been completely preserved in its original form.
History+
The construction of Favorite Palace took place between 1710 and 1730 under the direction of architect Johann Michael Ludwig Rohrer. The patron was Margravine Sibylla Augusta of Baden, widow of Margrave Ludwig Wilhelm. She had precise ideas for this total work of art, which was intended to serve as a rural pleasure palace alongside the residence in Rastatt. It was conceived for entertainment, social gatherings, hunting, masquerades, studies, and the education of her children.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Armin S.
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 48.8222, 8.2400