The Devetashka Cave is 18 km away. from the village of Krushuna (Krushuna waterfalls). It is one of the largest caves in Bulgaria. It was discovered in 1921. It is located about 15 km. northeast of Lovech, near the village of Devetaki on the east bank of the Osam River. Its size is huge. the total area is 20,400 m2.
The entrance is 35 meters wide and 30 meters high and takes you to a spacious hall of 2442 square meters.
– the largest cave foyer in Europe. The height of the hall in places reaches 100 meters. Extremely interesting are the seven openings in the ceiling through which the sunlight penetrates and illuminate the central hall and part of the two branches of the cave. As if you are in a church whose dome is cut by the rays of the sun. The largest of the openings is known as “Kilica”. After the central hall, the cave is divided into two branches. The left is about 2.5 km long. A small creek flows through it, forming a cascade of natural lakes and small waterfalls. The spring crosses the central hall and flows into the Osam River. The right branch of the cave is dry and warm and significantly smaller. It ends with a small circular gallery known as the Altar. The cave offers remarkably good living conditions – it is suitable for defense, it has large dimensions and natural lighting, clean river water. Probably because of these advantages it was inhabited in seven different eras, and in antiquity it was a cult place and served as a sanctuary.
Since 1967 the Devetashka Cave has been declared a cultural monument and since 1996 has been a protected natural site of international importance.
Due to the batch breeding period from June 1 to July 31, it is completely closed for visitors. Here are inhabited 12 species of protected amphibians, a mosquito smoker (included in the Red Book), a southern crested triton, a tree frog, a plain marsh turtle, a tortoise (imported into the World Red List), 82 species of birds in the area, 13 of which 34 species of mammals (4 of which were introduced in the Red Book of Bulgaria and 15 in the World Red List) and 9 bat species.
In the past the cave was used to store food from the state reserve. Then it is a classified military object.
In the 1950s, years have been used to store oil.