25 km cat­a­combs. Once these were sil­ver mines, then they began to be used for house­hold needs. In 1996, archae­ol­o­gists worked in the cat­a­combs, who record­ed that the sound of an organ was heard in the place indi­cat­ed by the leg­ends, and in one of the pas­sages, the researchers found a “lumi­nous stair­case” that emit­ted a red­dish light. Archae­ol­o­gists were exam­ined — mass hal­lu­ci­na­tions are exclud­ed. The rea­sons for the mys­te­ri­ous phe­nom­e­na are unknown.