It is located 23 kilometers northwest of the city of Drama and is the only exploited river cave in Greece. The natural entrance is the source of an underground river called Aggitis. The cave was passage or shelter people and animals in different eras. Near the present entrance for visitors, archaeological excavations brought to light important paleolithic and paleontological findings, which are in the Archaeological Museum of Drama. Human presence in the cave is known since prehistoric times. So far have been explored about 12 km and have been mapped 10 km route. Since 2000, started the operation of the cave, the visitor can admire the first 500m. of this unique phenomenon. The space is impressive in Cave and visitor, as he moves in a corridor over the river and against to the flow of water, monitors the natural decoration in the Cave which is dominated by white and red stalactites of various forms. The "Hall of the Wheel," which is currently associated with the main area of the cave with a corridor, owes its name to the presence of a large hydraulic wheel diameter 8m., which covered the water and irrigation needs of the region from the Ottoman era. Within this impressive hall opening in the roof, measuring 8x12m., possible entry of residents of surrounding villages and secret access from the citadel over the Cave into the river.Equally impressive is the arched opening where overflows with momentum the waters in the plain creating a cool oasis with trees, poplars and willows in the environment of cave, perfect for guests to relax. Inside the Cave nest occasionally or permanently live 37 kind of animals, mainly microfauna, of which six species became known for the first time in the international scientific community. We are finding also fish, bats and some larger mammals, such as otters and coypu.