The former ore mine "Theresia" is located in the district of Morshausen on the right slope of the Baybach Valley. From 1859 to 1886, ore was mined there. Initially in the "Upper" tunnel, which extends about 20 m into the mountain. However, to extract ore further inside the mountain, three additional access tunnels were created. The "Deep" tunnel is about 250 m long and runs approximately 100 m below the "Upper" tunnel.
Towards the end of World War II, the population of Morshausen sought refuge in the mine "Theresia" from artillery fire, which largely destroyed the village. Afterwards, the tunnel entrances were fitted with wooden doors to prevent entry into the dangerous tunnel passages. However, this was not successful in the long term. The doors were broken open several times.
