orecastorecast now has a new layer: caves & karst and old mining (adits, shafts, spoil heaps). That's more than 63,000 points across seven countries.
Old adits and shafts are tempting but genuinely dangerous: collapse, bad air and hidden drops. We flag those points with a clear warning. They're there to look at and understand, not to enter.
You'll find the new layer in the legend on the right of the map. Caves are blue, mining is rust-coloured, dangerous spots are red.
What sits behind the dots
The data comes from OpenStreetMap, which means years of survey work by people on the ground. By now it adds up to more than 147,000 points: around 103,000 caves and karst features, close to 30,000 mining objects and 14,000 officially listed geosites. The distribution follows the geology rather than the population. Caves cluster where limestone lies and water has dissolved it over millennia, on the Swabian Alb, in the Sauerland, in the Harz, in Franconian Switzerland. Mining points crowd the Ore Mountains, the Harz, the Siegerland and the Ruhr, where ore and coal came out of the rock for centuries.
Why we are blunt about old adits
An abandoned adit rarely looks dangerous, and that is exactly the problem. Carbon dioxide collects on the floor of old workings because it is heavier than air. Crouch down or step into a hollow and you breathe it without smelling a thing. Add rotten timber supports, hidden shafts under loose soil and water of unknown depth. Old mining also leaves crown holes, voids that work their way to the surface without warning. That is why these points are red and carry a plain warning.
The legal side
In Germany caves are protected biotopes under section 30 of the Federal Nature Conservation Act. Many are closed in winter because bats hibernate in them, and every disturbance costs an animal energy it cannot replace before spring. Mining structures fall under mining law and almost always sit on someone else's land. This layer is a map of what exists, not a route inside. If you want to see a cave from within, nearly every one of these regions has a show cave with a guide, and you will learn more there than alone with a torch.