The remains of the Abbey can be visited
Allerheiligen Abbey

The Allerheiligen Monastery, a former Premonstratensian canonry, is located in the Black Forest within the municipality of Oppenau.
History+
The Allerheiligen Monastery was founded around 1195 or 1196 by Duchess Uta von Calw, the widow of Welf VI. The foundation charter was confirmed by the Staufer Emperor Henry VI. Despite the involvement of leading noble families, the abbey, which was elevated to an abbey in 1657, remained regionally limited in its political importance. However, through pastoral care and a monastic school, it exerted influence on the central Black Forest.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://de.wikipedia.org/wiki/Datei:Allerheiligen_Klosterruine.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: 48.5373, 8.1941