Italy
Lapa do Salitre ("Saltpeter Cave"), also Lapa do Convento (Convent Cave), (BA-0166) is a limestone cave 5,670 meters long, near the municipality of Campo Formoso, in the state of Bahia, Brazil.
Listen to the audio guide for Lapa do Salitre Free on WIP — starts by itself when you arrive, even with the screen off