To be privately owned
Lautereck Castle

The moated castle Lautereck, also known as Teusser-Schlösschen, is in Löwenstein-Teusserbad. It is situated directly at the Teusser spring in the upper Sulm valley, which served as a sacred well even in pre-Roman times.
History+
Count Friedrich Ludwig von Löwenstein had the castle built in 1623 as a summer residence, within a lake of the then-spa facilities. The Teusser spring, where the castle stands, was already a sacred well in Germanic times and was probably also used by the Romans, as a connecting road ran nearby.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: https://commons.wikimedia.org/wiki/File:Loewenstein_Wasserschloss_Lautereck_20061202.jpg
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: 49.0949, 9.3748