Schloss Johannisburg is a castle in Aschaffenburg that was erected between 1605 and 1614 by Georg Ridinger. Until 1803, it was the second residence of the prince bishop of Mainz. It is constructed of red sandstone, the typical building material of the area around Aschaffenburg.
The castle is one of the main attractions of Aschaffenburg and its landmark. It is located in the center of the city, overlooking the waterside of the river Main. A keep from the destroyed 14th century castle that had formerly stood on the site was included in the construction and is the oldest part of the castle. Schloss Johannisburg is one of the most important buildings of the Renaissance period in Germany. At the end of the 18th century, the interior was restructured in the style of classicism.