mature tourists stand at the entrance to the kinderlinskaya cave and prepare to visit

achievement adventure attraction autumn bashkortostan biosphere caucasian cave cavity day deserted dungeon entrance entry excursion forest geological geology grotto hole inside karst kinderlinskaya landscape limestone mature mountain nature old opening outdoors passage people portal prepare rock route russia speleologist speleology spruce stand stone stones study success sunset surroundings tourism tourist tourists travel underground valley victory visit way window