About 300 meters upstream from the Apollo pit (where the Sosberger Bach is called Goschelbach for short before it becomes the Pfahlbach) a tunnel mouth opens directly on the gravel forest path in the rock. You can follow the tunnel for about 10 meters into the mountain, but it wasn't driven any further.
On the opposite side of the valley there are two tunnels in the slope above and below a rather overgrown farm road. Below the path there is an open tunnel that leads about 35 meters straight into the mountain. However, the surrounding slate rubble already points to the tunnel above it, which is located in a cut in the ground. The rubble area in front suggests a tunnel that leads far into the mountain, but unfortunately it is filled with water right from the start. There is no end in sight.