Museum
Deutschordenskommende Castle

The Teutonic Order Commandery in Koblenz was an establishment of the Teutonic Order, located at the confluence of the Moselle and Rhine rivers. This complex, parts of which are still preserved today, developed into a chamber bailiwick in the 15th century and now houses the Ludwig Museum.
History+
Archbishop Theoderich von Wied invited the Knights of the Teutonic Order to Koblenz in 1216, granting them an area of St. Castor's Church, including the St. Nicholas Hospital located there. The settlement of the order was also motivated by its capabilities in nursing. Soon after, an order establishment emerged directly at the mouth of the Moselle into the Rhine. By the mid-13th century, the order's importance in Koblenz grew, and the complex was expanded with the support of the Archbishops of Trier. The site was initially called “Deutscher Ordt,” later “Deutsches Eck.” In the 15th century, the commandery was elevated to a chamber bailiwick, directly subordinate to the Grand Master, controlling landholdings.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=614
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: 50.3628, 7.6050