Set up by the "Röttelnbund" in the state clerk's office (Landschreiberei), it houses important finds which have come to light in the course of the regular maintenance and restoration work. They show that life at Rötteln Castle was not just a military one. Not only cannonballs and arrow points, but also bowl fragments, oven tiles, buttons, scissors, thimbles and table bells are on display.
In addition, the museum provides vivid, descriptive insights into the castle's history. For example, a large model of the complex documents the last intact state in the mid-17th century, while engravings and graphics show other details of the castle. In some display cases the sagas surrounding the ruins are "illustrated".