B7-Höhle

The B7-Höhle is a limestone cave near Iserlohn-Grüne in the Arnsberg region. It was uncovered in 1965 during road construction work. The known length of the cave system reaches 5 100 metres. Its name comes from the nearby federal road B7. The surrounding area is protected as a nature reserve. The cave is not open to the public without guidance. Visitors must arrange tours through the visitor entrance of the Dechenhöhle, located about two kilometres west. The Dechenhöhle visitor centre provides details on available tours. Local caving groups such as the Speläogruppe Letmathe support exploration and documentation efforts. Inside, the B7-Höhle contains large chambers and narrow passages. Its walls show typical karst formations including stalactites and stalagmites. The cave system lies within a protected landscape noted for its geological features. Access remains restricted to organised tours to preserve the fragile environment.