The remains of the Castle can be visited
Helfenstein Castle

The Helfenstein Castle Ruin overlooks Geislingen an der Steige in Baden-Württemberg. It served as the ancestral seat of the Counts of Helfenstein and played a role in controlling traffic through the Filstal valley to the Alb plateau.
History+
Around the year 1100, Helfenstein Castle was constructed by Eberhard von Helfenstein. The Counts of Helfenstein, originating from this region, gained influence through their connections with the Staufer emperors. By the mid-14th century, they possessed a territory encompassing towns such as Geislingen, Heidenheim, Blaubeuren, and Wiesensteig.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://schloesserrundschau.de/bawue/schloesser/goeppingen04.html
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: 48.6162, 9.8471