Introduction to the Marienberg Fortress Castle: The Marienberg Fortress Castle (Festung Marienberg) towers above the Main River (Main). It combines defensiveness and beauty. It is a model of medieval castles. It was built as a Renaissance palace (Renaissanceschloss) and later converted into a Baroque fortress. In the inner courtyard of the castle you can visit the Margrave Palace Museum (Fürstenbaumuseum), which, in addition to precious furniture, tapestries and paintings, also houses the Marquis Hall (Fürstensaal) and the Margrave-Archbishop's Treasures and Religious Decoration Hall (Schatz- und Paramentenkammer).