The trails I ride in the Mullerthal area are somewhat technical and are full of natural obstacles like stones and tree roots but also small bridges, stepstones and stairs. The trails are winding through dense forests over rocky narrow paths and along babbling streams. The stairs are made by humans by cutting them out of the sandstone.
Sandstone is a relatively “soft” stone and will easily erode. Because of this erosion these rock will always be slippery in wet but also in dry conditions because of a layer of sand covering it. In a normal bike-crossing with a good tyre you will not experience any difficulties. But you have to be aware that a tyre will slip under heavy breaking. So look ahead to avoid heavy breaking actions.
These stairs will mean that you have to get off your bike now and then. Stairs of 4 á 5 steps will be doable riding upstairs but as soon as the steps are more than 5 you will have to walk and carry or shove your bike upwards. Just keep that in mind: a day of biking in the Mullerthal is also core stability training. Routes of 40-45 km are physically and time-wise maximum achievable.