This karst cave system is is believed to be more than 34 million years old. Though typically known as the Pertosa Caves, cave system is also known as Grotte dell'Angelo (Angel Caves), in honor of Saint Michael the Archangel, or Grotte di Pertosa-Auletta, for the two municipalities where most of the caves are located.

Almost two miles (three kilometers)  long and still not completely explored, the Pertosa Caves are connected with the phreatic zone of the Alburni Mountain range in southern Italy's Cilento and Vallo di Diano National Park. The water coming out of the phreatic zone forms an underground river that passes through the cave system and later joins the Tanagro River.

Thanks to this, the Pertosa Caves are among the few caves with a navigable stream. They're the only caves of their kind in Europe that are accessible to tourists. To visit the first section of the cave, you must take a boat that's pulled by a steel cable. The second part of the cave features a pedestrian path that winds between stalactites, stalagmites, and waterfalls.

Various vases and utensils dating back to the Stone Age and the Bronze Age have been found in the caves, leading to the hypothesis that the cavities were inhabited in prehistoric times. Today, the caves are not only a tourist attraction, but also a theater for productions inspired by Dante's Inferno and Homer's Odyssey.