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Duhlata Cave
Пещера Духлата
Relief Map of Bulgaria.jpg
Red pog.svg
Location of Duhlata Cave in Bulgaria
Location Bosnek, Pernik Province
Coordinates 42°29′41.64″N23°11′46.32″E / 42.4949000°N 23.1962000°E / 42.4949000; 23.1962000 Coordinates: 42°29′41.64″N23°11′46.32″E / 42.4949000°N 23.1962000°E / 42.4949000; 23.1962000
Length 18,200 m (59,700 ft)
Height variation 53 m (174 ft)
Access restricted

Duhlata (Bulgarian : Духлата) is a cave situated in Vitosha mountain, western Bulgaria. With a total length of 18,200 m, Duhlata is the longest cave in the country. It was declared a natural monument in 1962. The cave is home to six species of bats.

Bulgarian language South Slavic language

Bulgarian, is an Indo-European language and a member of the Southern branch of the Slavic language family.

Cave Natural underground space large enough for a human to enter

A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word cave can also refer to much smaller openings such as sea caves, rock shelters, and grottos, though strictly speaking a cave is exogene, meaning it is deeper than its opening is wide, and a rock shelter is endogene.

Vitosha mountain massif in Bulgaria

Vitosha, the ancient Scomius or Scombrus, is a mountain massif, on the outskirts of Sofia, the capital of Bulgaria. Vitosha is one of the symbols of Sofia and the closest site for hiking, alpinism and skiing. Convenient bus lines and rope ways render the mountain easily accessible. Vitosha has the outlines of an enormous dome. The territory of the mountain includes Vitosha nature park that encompasses the best known and most frequently visited parts. The foothills of Vitosha shelter resort quarters of Sofia; Knyazhevo quarter has mineral springs. Vitosha is the oldest nature park in the Balkans. The mountain emerged as a result of volcanic activity and has been subsequently shaped by the slow folding of the granite rock layers and a series of gradual uplifts of the area. It appears dome shaped at first sight, but the mountain, 19 km long by 17 km wide, actually consists of concentric denudational plateaus rising in tiers one above the other. Vitosha is separated into four main parts whose main ridges gather at a crown known as Cherni Vrah. This is the highest point of the mountain at 2290 m and is one of 10 peaks of Vitosha over 2000 m in height.



A view of the cave Main de Tangra dans la grotte de Duhlata.JPG
A view of the cave

Duhlata is situated in the south-western area of Vitosha on the left bank of the river Struma near the village of Bosnek, Pernik Province. The entrance of the cave is located at the very road between Bosnek and Chuypetlovo.

Struma (river) river in Bulgaria and Greece

The Struma or Strymónas is a river in Bulgaria and Greece. Its ancient name was Strymṓn. Its drainage area is 17,330 km2 (6,690 sq mi), of which 10,797 km2 (4,169 sq mi) in Bulgaria, 6,295 km2 (2,431 sq mi) in Greece and the rest in north Macedonia. It takes its source from the Vitosha Mountain in Bulgaria, runs first westward, then southward, forming a number of gorges, enters Greek territory at the Kula village. In Greece it is the main waterway feeding and exiting from Lake Kerkini, a significant centre for migratory wildfowl. The river flows into the Strymonian Gulf in Aegean Sea, near Amphipolis in the Serres regional unit. The river's length is 415 kilometres.

Pernik Province Province in Bulgaria

Pernik Province is a province in western Bulgaria, neighbouring Serbia. Its main city is Pernik, and other municipalities are Breznik, Kovachevtsi, Radomir, Tran, and Zemen.

Chuypetlovo Place in Pernik, Bulgaria

Chuypetlovo is a village in the Pernik municipality of Pernik Province, western Bulgaria. Its population is 57 as of January 2007.


The name of the cave originated from the sounds of the wind through its entrance, [1] from Bulgarian духам (transl. duham), meaning to whistle. Duhlata is 18,200 m long and 53 m deep. [2] The cave is well studied and mapped and boasts great diversity of speleothems. Duhlata is one of the most complex cave systems in Bulgaria and was created by underground currents of the Struma River. It is a maze of tunnels, galleries, underground lakes, waterfalls and sinter formations situated at seven levels. There are six subterranean rivers. [3]

Speleothem A structure formed in a cave by the deposition of minerals from water

Speleothems, commonly known as cave formations, are secondary mineral deposits formed in a cave. Speleothems typically form in limestone or dolostone solutional caves. The term "speleothem" as first introduced by Moore (1952), is derived from the Greek words spēlaion "cave" + théma "deposit". The definition of "speleothem" in most publications, specifically excludes secondary mineral deposits in mines, tunnels and on man-made structures. Hill and Forti more concisely defined "secondary minerals" which create speleothems in caves as;

A "secondary" mineral is one which is derived by a physicochemical reaction from a primary mineral in bedrock or detritus, and/or deposited because of a unique set of conditions in a cave; i.e., the cave environment has influenced the mineral's deposition.

It is home to 22 species of known animal species, including six bat species. [1] The stygofauna include 11 Copepods, 2 Amphipoda, 1 Syncarida and 1 Acari species, and the only species of the troglofauna is the pseudoscorpion Neobisium kwartirnikovi. The diversity of worms (Nematoda, Oligochaeta), snails (Mollusca) and seed shrimps (Ostracoda) has not been studied. [3]

Bat Order of flying mammals

Bats are mammals of the order Chiroptera; with their forelimbs adapted as wings, they are the only mammals naturally capable of true and sustained flight. Bats are more manoeuvrable than birds, flying with their very long spread-out digits covered with a thin membrane or patagium. The smallest bat, and arguably the smallest extant mammal, is Kitti's hog-nosed bat, which is 29–34 mm (1.14–1.34 in) in length, 15 cm (5.91 in) across the wings and 2–2.6 g (0.07–0.09 oz) in mass. The largest bats are the flying foxes and the giant golden-crowned flying fox, Acerodon jubatus, which can weigh 1.6 kg (4 lb) and have a wingspan of 1.7 m.

Stygofauna animals living in subterranean waters

Stygofauna are any fauna that live in groundwater systems or aquifers, such as caves, fissures and vugs. Stygofauna and troglofauna are the two types of subterranean fauna. Both are associated with subterranean environments – stygofauna are associated with water and troglofauna with caves and spaces above the water table. Stygofauna can live within freshwater aquifers and within the pore spaces of limestone, calcrete or laterite, whilst larger animals can be found in cave waters and wells. Stygofaunal animals, like troglofauna, are divided into three groups based on their life history - stygophiles, stygoxenes and stygobites.

  1. Stygophiles inhabit both surface and subterranean aquatic environments, but are not necessarily restricted to either;
  2. Stygoxenes are like stygophiles, except they are defined as accidental or occasional presence in subterranean waters. Stygophiles and stygoxenes may live for part of their lives in caves but do not complete their life cycle in them; and
  3. Stygobites are obligate or strictly subterranean, aquatic animals and complete their entire life in this environment.
Copepod subclass of crustaceans

Copepods are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic, some are benthic, and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, and puddles, damp moss, or water-filled recesses (phytotelmata) of plants such as bromeliads and pitcher plants. Many live underground in marine and freshwater caves, sinkholes, or stream beds. Copepods are sometimes used as biodiversity indicators.

Access to the cave is restricted. Duhlata can be visited only by researchers or experienced cavers with permission by Vitosha Nature Park Directorate. [1] [3]

See also

Geography of Bulgaria Information about the geographical make-up of Bulgaria, including topology

Bulgaria is a country situated in Southeast Europe, bordering Romania to the north, Serbia and North Macedonia to the west, Greece and Turkey to the south, and the Black Sea to the east. The northern border with Romania follows the river Danube until the city of Silistra. The land area of Bulgaria is 110,879 square kilometres (42,811 sq mi), slightly larger than that of Iceland or the U.S. state of Tennessee. Considering its relatively small size, Bulgaria has a great variety of topographical features. Even within small parts of the country, the land may be divided into plains, plateaus, hills, mountains, basins, gorges, and deep river valleys. The geographic center of Bulgaria is located in Uzana.


  1. 1 2 3 "Duhlata Cave". Get to know Bulgaria (in Bulgarian). Retrieved 16 February 2016.
  2. "Duhlata Cave". The Caves in Bulgaria. Retrieved 16 February 2016.
  3. 1 2 3 "Protected areas". Official site of Vitosha Nature Park (in Bulgarian). Retrieved 16 February 2016.

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