Lukenloch Karst Sinkhole

In the middle of the forest between Schlangen and Feldrom is the "Lukenloch". According to an old story, the Lukenloch was used as a site for an early medieval Saxon sanctuary. The formation of the natural monument can be explained by seeping rainwater, which dissolved the limestone in the ground. Sinking cold air collects in the Lukenloch and offers bats an ideal resting place in these damp and cold conditions. The area around the cave is fenced off. Entering this funnel-shaped cave, which is several meters deep and is located in the "Bielsteinhöhle mit Lukenloch" FFH area is prohibited.
(see Lipperland.de)

At the hatch hole you can only see the entrance hole of the 27 m deep funnel cave.
Of course it is locked for safety reasons.

Lukenloch (funnel-shaped karst hole), cool and humid wintering quarters for bats, not accessible. Board explains the origin of the cave and its importance for nature conservation.