The "Old Salt Works" is not only from outside impressive. You really get to know the building making a guided tour through the ramified tunnel system.
The guided tour starts above ground with the powerful constant rotating water wheels. After a few stairs you will be in the fascinating world below ground. Passing drive linkages and bell cranks you reach the popular highlights like the grot of the salt works, the "Karl-Theodor-Pump" and the relief of elector Karl Theodor. Via a shaft you reach the salt museum.