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DF2014:Dwarf cancels task: Dangerous terrain
|This article is about the current version of DF.|
This message means that the path a dwarf has chosen has become occupied with deep water or magma, or the dwarf is no longer on solid ground. In the case of water, dwarves will path through water at depths of [3/7] or shallower. Dwarves cancel their task if confronted with water that is [4/7] or deeper. This often happens when players are slowly filling accessible pools or moats or what have you. As the dwarves attempt to cross the body of water during the filling, they will be interrupted by any tiles of [4/7] water sloshing around. Magma of course can also flow across a dwarf's path and cause a cancellation, but for magma it only requires a depth of [1/7].
If a miner channels the floor out from under another dwarf the latter will cancel because of "dangerous terrain". The same will apply if a dwarf opens a floor hatch that another dwarf was standing upon, or if any mechanically-operated buildings cease to provide a walkable surface.
Solid furniture without a "walkable" surface also counts as dangerous terrain. For instance, a dwarf standing on the top of a raised bridge will cancel its job, with this cancellation message. Trees growing through bridgesBug:7872 can override the "walkable" tag, leading to dangerous terrain complaints.
Fortresses with waterfalls near high traffic areas or meeting areas can generate these messages with annoying frequency, though it can be amusing to see "Dwarf cancels Attend Party: Dangerous terrain" when a partygoer steps underneath the waterfall in your dining room or sculpture garden. To limit warnings caused by waterfalls you can reduce the amount of water in motion and/or block frequently-inundated tiles with a statue or fortification.
It can also mean the dwarf is currently in dangerous terrain, and is canceling a job on the other side of the map or that the dwarf requires building materials that are at the bottom of a lake or river.
If there is a river on your map with treacherous carp, this is often the message which heralds yet another of your dwarves drowning due to being yanked in by fish. Fun.