The "Mühlsteinwanderweg" was created on the initiative of the Mühlsteinreviers RheinEifel and is a 13-kilometre hiking trail from the Mayen pit field via the Ettringer Lay, the Kottenheimer Winfeld past the Mendiger Tonsee to the Michels farm in Mendiger Brauerstraße - but it can easily be walked in both directions.

Numerous basalt steles with information boards along the trail provide an overview of the historical development of the millstone and provide information about the importance of the millstone for the region, the extraction and distribution areas.

The local basalt lava has been quarried in our region for almost 7,000 years, both industrially and individually. The lava is suitable for a wide range of industrial products - one of which is the millstone. In order to preserve a lasting memory of this unique workpiece, which is so important for the development of mankind, the "Millstone Hiking Trail" was initiated.

The "Millstone Hiking Trail" begins at the "Erlebniswelten Grubenfeld" in the Mayener Grubenfeld and leads from there, initially ascending steadily for approx. 3.5 kilometers to the highest point of the trail in the direction of "Ettringer Bellerberg".

On the flank of the Bellerberg, the trail descends to the "Ettringer Lay". The "Ettringer Lay" is a quarry area of the modern stone industry. The disused quarries of the "Ettringer Lay", which have been reclaimed by nature, are part of the volcano park as a volcano park station. Steel figures along a circular path show the typical activities in a quarry. Further information on the eruption of the Bellerberg volcano and modern quarrying activities is provided on information boards. The former quarry walls are now also used as a climbing area by the German Alpine Club.

This route is a branch trail and, after visiting the impressive basalt walls in the "Ettringer Lay", leads back along the flank of the Bellerberg with fantastic views back to the signposted crossroads. Keep left here and walk past a former air raid shelter before continuing up over the ridge of the "Kottenheimer Büden" and along the edge of the crater. The "Kottenheimer Büden" is the eastern flank of the Bellerberg volcano. After a short, steep descent, you reach a wide path which you follow to the left.

After crossing the K20, keep right and walk past an old restored compressor house into the "Kottenheimer Winfeld". Here the path leads past an area that is currently being restored to its former glory by the "Heimatverein Kottenheimer Winfeld". As there is currently still a construction site here, this area is not open to the public.

The route continues parallel to the so-called "embroidered road", which probably dates back to the 19th century, past Junker-Schilling-Platz and the Mendiger Tonsee in the Winkelswiesen (private property).

The path now leads steadily downhill across fields and meadows to the lowest point of the route shortly before reaching the village of Mendig. After approx. 10 km of the route, the ascent to Obermendig follows. The route then crosses the town of Mendig. In Niedermendig, you finally reach the end of the route, the Michels farm in Brauerstraße. Guided tours of the lava cellar there can be booked at the Lava Dome. A detour to the "Mendiger Museumslay" is also possible from here. This open-air exhibition, which is accessible free of charge, shows how the so-called layers - the miners - extracted basalt lava, brought it to the surface and processed it there. Among other things, you can see a shovel, a faithfully reconstructed forge, a stonemason's hut and a pit crane.