Devetashka cave is located approximately 2 km (1.2 mi) from the village of Devetaki. A narrow path by the river leads from the village to the cave. It can also be accessed directly via Road 301 along a 400 m (1,300 ft) long dirt road and a concrete bridge. Now part of a public park, that includes a waterfall, the 2 km (1.2 mi) long karst cave formed from the dissolution of soluble rocks, characterized by sinkholes and an underground river. It is rich in speleothems, stalagmites, stalactites, countless rivulets and majestic natural domes.
The site is 35 m (115 ft) wide and 30 m (98 ft) high at the entrance. The cave widens after around 40 m (130 ft), forming a spacious hall with an area of 2,400 m2 (26,000 sq ft), a height of 60 m (200 ft) that can reach up to 100 m (330 ft). Several large openings in the ceiling allow daylight to lighten the vast interior, due to commercial use of the site during the 1950s.
Rediscovered in 1921, excavations began only in the 1950s and revealed almost continuous human occupation since the late Paleolithic. Earliest traces of human presence date back to the Middle Paleolithic around 70,000 years ago. The site also contained one of the richest sources of Neolithic cultural artifacts (6,000 to 4,000 BC).
Besides significant archaeological findings, Devetashka cave provides a habitat for a wide diversity of faunal residents. During the breeding season of mammalian species in the cave from early June to the end of July, the site is entirely closed to visitors. Twelve species of protected amphibians and reptiles, including the Aesculapian snake (Zamenis longissimus), the Triturus (Triturus cristatus), the European tree frog (Hyla arborea), Hermann’s tortoise (Testudo hermanni), eighty-two bird species can be found in the area, thirteen of which are included in the Red List. Thirty-four species of mammals, four of which are included in the Red List and fifteen species of bats are to be found at the Devetashka cave.