|This article is about an older version of DF.
A cave is a natural formation that occurs in or adjacent to any non-mountain region tile, consisting of a 48x48 tile wide site within the non-mountain biome. Caves most often feature a large rock mound several z-levels high with a downward passage beginning anywhere along the side of the mound. Caves often, but not always, have deep passages that lead down into caverns; they may also lack any passages or, more rarely, entrances into the mound itself.
In Dwarf Fortress Mode, you can can choose whether or not to make caves visible on the embark screen when you design the world you will play in. The default option for Make Caves Visible is set to No. Caves have the odd feature that the stone they are made of doesn't match the material left after it is dug out; for example, a rock wall will leave behind a clay floor.
Caves are sometimes home to named creatures and semimegabeasts such as ettins. If a cave is inhabited by creatures fond of stealing items from nearby sites, their hoard will be littered over the area. The distribution of plunder remains within the 48x48 site, from the upper z limit down to any z-levels reachable by walking (no more loot will be found beyond a rampless drop or a waterlogged passage, even if the hoard's owner is a flying creature.) Dragons are known to hoard jewelry, ettins and giants hoard jewelry, food and booze.
In adventure mode (as of v0.31.17) caves can sometimes be found by repeatedly asking an NPC about the surroundings. They're the only way of entering the underworld in adventure mode (besides visiting an abandoned fortress which has an entrance to a cavern), so if NPCs in one region don't tell you about any caves move to another region and try again.
Before v0.31.17[Verify] caves could be found by asking for quests, and would often contain many stolen crafts which could be sold at shops.