The remains of the Castle can be visited
Achalm Castle (Ruin)

The Achalm ruin is a landmark of the city of Reutlingen. As a hilltop castle, it offers a wide view over the landscape of Baden-Württemberg.
History+
Between 1030 and 1050, the castle was built by Counts Egino and Rudolf von Achalm. It was first documented in 1090. In the same century, the complex was expanded with a lower castle. After a period during which the castle belonged to the Welfs, it passed into the possession of the Counts of Württemberg in 1376. By 1498, the castle was in a poor structural condition and was finally demolished around 1650.
Source: Wikipedia · Licence: CC BY-SA 4.0
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: 48.4941, 9.2440