The tunnel mouth is about 50m from the path of the dream loop (forest path) away above the slope behind the fenced garden plots on a forgotten and overgrown farm road.
After the low entrance, you come across a rusty ladder after 10 meters and only looking back reveals that the entrance was probably earlier.
Then it gets exciting, because it's a bit slippery on a slope 15 meters further and a good 5 meters down(!). If you are at the bottom, turn left at right angles. This level leads through several excavation rooms, which are wide but not high, a good 70 meters far into a dome that is also low, from which tunnels lead off on both sides. But you can also go straight ahead 60 meters, then you would have to go through knee-deep water for a good 20 meters and then you might have to go further. The tunnel to the right leads 50 meters to a cathedral and then another 50 meters further. The left tunnel ends after about 45 meters.
So you have a lot to do!