The former ore mine "Theresia" is located in the district of Morshausen in the right Baybach valley slope. Ore was mined there from 1859 to 1886. Initially in the "Upper" adit, which reached about 20 meters into the mountain. However, in order to be able to extract ore further inside the mountain, three additional access tunnels were built. The "Deep" adit is about 250 m long and runs about 100 m below the "Upper" adit. Towards the end of the Second World War, the population of Morshausen sought shelter from artillery fire in the "Theresia" mine, which destroyed most of the village. Afterwards, the entrances to the mine were equipped with wooden doors to prevent people from entering the dangerous tunnels. However, this was not successful in the long run. The doors were broken open several times.