The remains of the castle can be visited
Besserstein Castle
In Villigen in the canton of Aargau, Switzerland, the Besserstein castle ruin, a former hilltop castle, is located on the Geissberg. Only a few remnants are visible today.
History+
The origins of Besserstein Castle are obscure, but its first documented mention occurred in 1244 as a fief of Murbach Abbey, which also owned the Rein estate. In February 1259, the castle was the site of a meeting between Count Rudolf of Habsburg and his cousin Gottfried of Habsburg-Laufenburg. In the course of this, the Habsburgs renounced the bailiwick of St. Amarintal in favor of Murbach Abbey in April of the same year.
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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: 47.5244, 8.2115