Between the three Eifel towns of Müllenbach, Laubach and Leienkaul lies the spectacular Kaulenbach Valley, where quality roofing slate was once mined. The Schieferregion Kaulenbachtal hiking loop is a 14.2 km trail that starts in one of three idyllic Eifel villages: Müllenbach, Laubach or Leienkaul. A highlight of the route is the monastery and pilgrimage church of Maria Martental, which dates back to 1140. Kaulenbach Valley was once one of the most famous slate quarries in the slate mountains on the left bank of the Rhine. Until 1959, top quality roofing slate was mined in Kaulenbach Valley. Due to a water ingress at the Maria-Schacht mine, however, mining was stopped. Since then, the Kaulenbach Valley has become a refuge for rare and endangered animal and plant species. For example, the thermophilic wall lizards now live in ideal conditions in the mighty spoil heaps and bats find a protected place in the numerous tunnels during the winter months.

Also of interest are the remains of the former mines, which bear witness to the history of slate mining in the region. For this reason, the Kaulenbach Valley was declared a Nature Reserve in 1988 and a listed landmark area in 1993. Since then, many remains of buildings and dry stone walls have been protected from decay. Mine entrances have been opened and slate heaps gave been cut free, and a hiking loop trail has been created. Information boards with details about slate mining, old photographs and floor plans of mines, as well as old mine cars ("Hunte", in the miners' vernacular) with which the Mosel slate was transported, give small insights. A special highlight is the reconstructed splitting house opened in 2016!

Take advantage of the offer of a guided hike by expert guides from the "Verein zur Erhaltung der Schieferbergbaugeschichte" (Association for the Preservation of Slate Mining History) - register with Rolf Stoll at 0157-39343224.