Karst is a topography formed from the dissolution of soluble carbonate rocks such as limestone, dolomite, and gypsum. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. It has also been documented for more weathering-resistant rocks, such as quartzite, given the right conditions. Subterranean drainage may limit surface water, with few to no rivers or lakes. However, in regions where the dissolved bedrock is covered or confined by one or more superimposed non-soluble rock strata, distinctive karst features may occur only at subsurface levels and can be totally missing above ground.
A subterranean river is a river that runs wholly or partly beneath the ground surface – one where the riverbed does not represent the surface of the Earth. It is distinct from an aquifer, which may flow like a river but is contained within a permeable layer of rock or other unconsolidated materials. A river flowing below ground level in an open gorge is not classed as subterranean.
The Una is a border river between Bosnia and Herzegovina and Croatia and a right tributary of the Sava river. It is part of the Black Sea drainage basin, and its watershed has a size of 10,200 km2 (3,900 sq mi), of which 8,080 km2 (3,120 sq mi) belongs to Bosnia and Herzegovina, and 2,120 km2 (820 sq mi) to Croatia. The total length of the river is 212 km (132 mi). The source of the river is located in the town of Donja Suvaja in Croatia, and its mouth is located near the town of Jasenovac, on the border with Bosnia. The largest right tributaries are the Krka, Unac, Krušnica and Sana rivers, and the largest left tributary is the Klokot river. Its longest headwater is the Unac river. The largest and most important city located on the river is Bihać. Other, important cities and towns are Bosanska Krupa, Bosanski Novi and Bosanska Kostajnica. The river is characterized by a multitude of waterfalls, rapids, karst springs and relatively untouched nature. A large part of the upper river is part of the Una National Park.
The Krka is a river in southeastern Slovenia, a right tributary of the Sava. With a length of 94.6 km (58.8 mi), it is the second-longest river flowing in its entirety in Slovenia, following the Savinja.
The Trebišnjica is a river in Bosnia and Herzegovina. It used to be a sinking river, 96.5 km (60.0 mi) long above the ground. With a total length of 187 km (116 mi) above and under the ground, it is one of the longest sinking rivers in the world.
Postojna Cave is a 24,340 m (79,860 ft) long karst cave system near Postojna, southwestern Slovenia. It is the second-longest cave system in the country as well as one of its top tourism sites. The caves were created by the Pivka River.
The Lahinja is a river in White Carniola, the extreme southeastern part of Slovenia. It is 34 kilometres (21 mi) long and originates from several karst springs at the end of a steephead valley between the villages of Knežina, Belčji Vrh, and Mali Nerajec.
A ponor is a natural opening where surface water enters into underground passages; they may be found in karst landscapes where the geology and the geomorphology is typically dominated by porous limestone rock. Ponors can drain stream or lake water continuously or can at times work as springs, similar to estavelles. Morphologically, ponors come in forms of large pits and caves, large fissures and caverns, networks of smaller cracks, and sedimentary, alluvial drains.
Škocjan Caves is a cave system in Slovenia. Due to its exceptional significance, Škocjan Caves was entered on UNESCO’s list of natural and cultural World Heritage Sites in 1986. International scientific circles have thus acknowledged the importance of the caves as one of the natural treasures of planet Earth. Ranking among the most important caves in the world, Škocjan Caves represents the most significant underground phenomena both on the Karst Plateau and in Slovenia. Following independence from Yugoslavia in 1991, Slovenia committed itself to actively protecting the Škocjan Caves area and established Škocjan Caves Regional Park and its managing authority, the Škocjan Caves Park Public Service Agency.
Klošter is a settlement on the left bank of the Lahinja River in the Municipality of Metlika in the White Carniola area of southeastern Slovenia. The entire area is part of the traditional region of Lower Carniola and is now included in the Southeast Slovenia Statistical Region.
Mala Lahinja is a settlement at the source of the Lahinja River south of Dragatuš in the Municipality of Črnomelj in the White Carniola area of southeastern Slovenia. The area is part of the traditional region of Lower Carniola and is now included in the Southeast Slovenia Statistical Region.
Škocjan Caves Regional Park is located in the Škocjan Karst, a vast flat landscape that lies at an elevation between 420 and 450 m in the southeast part of the Karst area. Following its independence, the Slovenia committed itself to protecting the Škocjan Caves area; for this reason, it established Škocjan Caves Regional Park and its managing authority, the Škocjan Caves Park Public Service Agency.
A karst spring or karstic spring is a spring that is part of a karst hydrological system.
Krupa is a small village in the Municipality of Semič in Slovenia. It lies at the source of the Krupa River, a left tributary of the Lahinja River. The area is part of the historical region of White Carniola. The municipality is now included in the Southeast Slovenia Statistical Region.
Moverna Vas is a small village in the Municipality of Semič in Slovenia. It lies on the left bank near the source of the Krupa River, a left tributary of the Lahinja River. The area is part of the historical region of Lower Carniola. The municipality is now included in the Southeast Slovenia Statistical Region.
The Cliefden Caves is a heritage-listed geoheritage site in Mandurama, Cowra Shire, New South Wales, Australia. The caves comprise Ordovician fossil localities, limestone caves, a spring and tufa dams, and a site where limestone was first discovered in inland Australia.
The Lož Karst Field, also known as the Lož Valley, is a karst field in Inner Carniola in southwest Slovenia. It is the smallest karst field in Inner Carniola.
The Dobličica is a stream in White Carniola. It is part of a karst aquifer. Due to its geological and hydrological characteristics and urbanization of the area, it is considered sensitive and subject to pollution.
The Račna Karst Field is a karst field in the northern edge of the Lower Carniolan karst area, south of Grosuplje, Slovenia. It has rich natural and cultural value. Because of its ecological significance, it is anticipated that a nature park will be established there and that it will be included in the Natura 2000 program.
Krka Cave is a horizontal karst cave and an occasional source of the Krka River in Dry Carniola, central Slovenia. It lies in a pocket valley between the villages of Trebnja Gorica to the east and Gradiček to the west, north of the village of Krka. Water flows into the cave from the Račna Karst Field south of the town of Grosuplje and emerges a few metres below the cave's main entrance in the karst spring of the Krka. The cave, which is of archaeological and historical significance and features great fauna diversity, is open to announced tourist visits in the presence of a guide and also used as an event venue.
