Editing 40d:Underground river

{{Quality|Exceptional|17:03, 6 January 2014 (UTC)}}
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'''Underground rivers''' occur in almost every region with a [[mountain]] biome, similar to the appearance patterns of [[adamantine]]. Upon discovering an underground river, subterranean plants will begin growing in suitable locations (on muddy floors, and on soil floors with a soil wall nearby beneath them).

On maps without a river, brook, any underground [[soil]] or aboveground plants to gather (so you can therefore get their seeds and begin [[farming]] aboveground) these can be a blessing since they provide water for muddying tiles (allowing both farming and [[plant gathering]] underground), but on others they can be a hindrance, because you have to dig around them.

An underground river (or an [[underground pool]]) also allows you to build an underground [[tree farm]], which is handy and safe on maps without trees or with dangerous wildlife.

The underground river is populated with [[frogman|frogmen]], [[lizardman|lizardmen]], [[snakeman|snakemen]], [[olmman|olmmen]], [[cave crocodile]]s, [[giant toad]]s, [[giant olm]]s, and [[mud man|mud men]]. These can interrupt the work of any [[dwarf]] within line of sight, and can thus be a real nuisance.

[[Cave spider]]s are a type of [[vermin]] that occur near underground rivers. They leave small webs strewn around, which can be collected for [[silk]] [[Weaver|weaving]]. Fisherdwarves may also be able to catch [[cave fish]] and [[cave lobster]]s from the river itself (though not from other water tiles nearby), and [[olm]]s may occasionally be found walking around (and potentially getting caught in cave spider webs).

The [[water]] sources for underground rivers, if any are present, are [[waterfall]] tiles from nowhere.

Underground rivers are 2 to 5 tiles wide and while they often flow in a straight line, they can twist and turn across the entire map, spanning multiple levels.

{{Category|World}}
[[ru:Underground river]]