Subterranea are ''underground structures'', both natural (such as

cave 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 refer to smaller openings such as sea ...

s) and human-made (such as mines). Some subterranea and related topics include:

Natural

Cave 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 refer to smaller openings such as sea ...

s **

Cenote A cenote ( or ; ) is a natural pit, or sinkhole, resulting from the collapse of limestone bedrock that exposes groundwater. The regional term is specifically associated with the Yucatán Peninsula of Mexico, where cenotes were commonly used for ...

Ice cave An ice cave is any type of natural cave (most commonly lava tubes or limestone caves) that contains significant amounts of perennial (year-round) ice. At least a portion of the cave must have a temperature below 0 °C (32 °F) all ...

Sea cave A sea cave, also known as a littoral cave, is a type of cave formed primarily by the wave action of the sea. The primary process involved is erosion. Sea caves are found throughout the world, actively forming along present coastlines and as relic ...

Sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

Karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

Lava tube A lava tube, or pyroduct, is a natural conduit formed by flowing lava from a volcanic vent that moves beneath the hardened surface of a lava flow. If lava in the tube empties, it will leave a cave. Formation A lava tube is a type of lava ca ...

Lunar Lunar most commonly means "of or relating to the Moon". Lunar may also refer to: Arts and entertainment * ''Lunar'' (series), a series of video games * "Lunar" (song), by David Guetta * "Lunar", a song by Priestess from the 2009 album ''Prior t ...

and Martian lava tubes *

Subterranean river 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 per ...

Subterranean waterfall A subterranean waterfall or underground waterfall is a waterfall located underground, usually in a cave or mine.

Underground lake An underground lake or subterranean lake is a lake underneath the surface of the Earth. Most naturally occurring underground lakes are found in areas of Karst topography, where limestone or other soluble rock has been weathered away, leaving a cav ...

Volcanic pipe Volcanic pipes or volcanic conduits are subterranean geological structures formed by the violent, supersonic eruption of deep-origin volcanoes. They are considered to be a type of ''diatreme''. Volcanic pipes are composed of a deep, narrow cone o ...

Human-made or related

Borehole A borehole is a narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water ( drilled water well and tube well), other liquids (such as petrol ...

Bunker A bunker is a defensive military fortification designed to protect people and valued materials from falling bombs, artillery, or other attacks. Bunkers are almost always underground, in contrast to blockhouses which are mostly above ground. ...

Burial vault (tomb) A burial vault is a structural underground tomb. It houses the casket and protects them through a lined, sealed container. A burial vault shields the casket from maintenance equipment and resists water. Different levels of burial vaults are off ...

Casemate A casemate is a fortified gun emplacement or armored structure from which artillery, guns are fired, in a fortification, warship, or armoured fighting vehicle.Webster's New Collegiate Dictionary When referring to Ancient history, antiquity, th ...

Catacombs Catacombs are man-made subterranean passageways for religious practice. Any chamber used as a burial place is a catacomb, although the word is most commonly associated with the Roman Empire. Etymology and history The first place to be referred ...

Cave dweller A cave dweller, or troglodyte, is a human being who inhabits a cave or the area beneath the overhanging rocks of a cliff. Prehistory Some prehistoric humans were cave dwellers, but most were not (''see'' ''Homo'' and Human evolution). Such ...

Underground living Underground living refers to living below the ground's surface, whether in natural or manmade caves or structures. Underground dwellings are an alternative to above-ground dwellings for some home seekers, including those who are looking to mini ...

* Cave temple * Cellar *

Dungeon A dungeon is a room or cell in which prisoners are held, especially underground. Dungeons are generally associated with medieval castles, though their association with torture probably belongs more to the Renaissance period. An oubliette (from ...

Dugout (shelter) A dugout or dug-out, also known as a pit-house or earth lodge, is a shelter for humans or domesticated animals and livestock based on a hole or depression dug into the ground. Dugouts can be fully recessed into the earth, with a flat roof cover ...

Fogou A fogou or fougou (pronounced "foo-goo") is an underground, dry-stone structure found on Iron Age or Romano-British-defended settlement sites in Cornwall. The original purpose of a fogou is uncertain today. Colloquially called , , , giant holts ...

Mine Mine, mines, miners or mining may refer to: Extraction or digging * Miner, a person engaged in mining or digging *Mining, extraction of mineral resources from the ground through a mine Grammar *Mine, a first-person English possessive pronoun ...

Rock cut architecture Rock-cut architecture is the creation of structures, buildings, and sculptures by excavating solid rock where it naturally occurs. Intensely laborious when using ancient tools and methods, rock-cut architecture was presumably combined with quarry ...

rock-cut tomb A rock-cut tomb is a burial chamber that is cut into an existing, naturally occurring rock formation, so a type of rock-cut architecture. They are usually cut into a cliff or sloping rock face, but may go downward in fairly flat ground. It was a ...

Smuggling tunnel Smuggling tunnels are secret passages used for the smuggling of goods and people. The term is also used where the tunnels are built in response to a siege. Europe Bosnia The Sarajevo Tunnel operated during the Siege of Sarajevo as a pass ...

Tunnel A tunnel is an underground passageway, dug through surrounding soil, earth or rock, and enclosed except for the entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube cons ...

s (street tunnel, train tunnels) *

Underground city An underground city is a series of linked subterranean spaces that may provide a defensive refuge; a place for living, working or shopping; a transit system; mausolea; wine or storage cellars; cisterns or drainage channels; or several of thes ...

, umbrella article for underground dwellings and facilities * Underground rapid transit system *

Wine cave Wine caves are subterranean structures for the storage and the aging of wine. They are an integral component of the wine industry worldwide. The design and construction of wine caves represents a unique application of underground construction ...

Natural

Human-made or related

See also