Over the decades, students “decorated “ the prison with graffiti, eventually covering everything (and I do mean everything; walls, ceilings, floors, stairwells, etc). Some of this “artwork” is quite amazing.
The prison was finally closed in 1914 and is now a tourist attraction. Located behind the University of Heidelberg Museum, it is open most days (except Monday). This HAS to be visited if you go the Heidelberg. We loved it!