Hosta

Subterranean river in Castellet-lès-Sausses

Subterranea are underground structures, both natural (such as caves) and human-made (such as mines).^{[citation needed]} Some subterranea and related topics include:

Natural

• Caves
  • Cenote
  • Ice cave
  • Sea cave
  • Sinkhole
• Karst
• Lava tube
  • Lunar and Martian lava tubes
• Subterranean river
• Subterranean waterfall
• Underground lake
• Volcanic pipe

Human-made or related

• Borehole
• Bunker
• Burial vault (tomb)
• Casemate
• Catacombs
• Cave dweller, Underground living
• Cave temple
• Cellar
• Dungeon
• Dugout (shelter)
• Fogou
• Hypogeum
• Mine
• Rock cut architecture, rock-cut tomb
• Smuggling tunnel
• Tunnels (street tunnel, train tunnels)
• Underground city, umbrella article for underground dwellings and facilities
• Underground rapid transit system
• Wine cave

See also

• Boring (earth)
• Seattle Underground
• Subterranean London