Lepenitsa cave is located in the Western Rhodopes at the foot of Mount Sutkja. It is around 10 km southeast of the town of Rakitovo. Before 1925 Lepenica had not been visited. The first photos and mapping were done by the engineer Pavel Petrov and later it was studied and mapped by Prof. Peter Tranteev. 1356 m of the cave, which has a total length of 1525 m, are surveyed and mapped. The cave association in Rakitovo made a second entrance to the cave, because the natural one was buried in water. There were plans to build a hut, but they remain unfulfilled. The cave was declared a natural landmark on 10 October 1962.
The entrance to the cave is only one meter high and has a very inclined profile. Lepenitsa river runs along the bottom floor of the cave. On the middle cave floor there is a wide variety of cave formations and there are four lakes in rainy weather, and in dry weather two remain. Speleologists have found seven pearls – some of the rarest natural specimens that are in the Natural History Museum in Sofia. Approximately 500 meters inward, Lepenica hasn’t been explored. Many of the rock formations there are broken and the walls are smoked. Due to the difficult passage the cave is Lepenitsa has self-protected.
The cave fauna is extremely rich and interesting. There are 20 species of cave animals, among them eight bat species. According to Peter Beron, in Lepenitsa there are four species of animals that are not found anywhere else in the world. Up to date, 24 species of animals have been studied there, of which 6 have been categorized as troglobites (living only in caves).
The cave is a shelter for 7 different bat species, which occupy it during different seasons. The following species have been observed there:
- Greater horseshoe bat (Rhinolophus ferrumequinum)
- Lesser horseshoe bat (Rhinolophus hipposideros)
- Geoffroy’s bat (Myotis emarginatus)
- Greater mouse-eared bat (Myotis myotis)
- Lesser mouse-eared bat (Myotis blythii)
- Western barbastelle (Barbastella barbastellus)
- Grey long-eared bat (Plecotus austriacus)
Six of the species are prioritized for protection in the whole of Europe – the Greater horseshoe bat, the Lesser horseshoe bat as well as the three Myotis species. The cave is the main shelter for three of the bat species, living in its region – the two horseshoe bat species as well as Myotis myotis.