; The road would be too steep to traverse.
: Cannot dig a cobblestone road to over 20 slope steep.
; The water is too deep or too shallow to dig using that tool
: You can only dig 7 dirt below water level with a shovel before you have to switch to a [[dredge]].
; You are not allowed to drop dirt there.
: Cannot drop dirt on cobblestone road when the corner is surrounded on all sides by trees or similar tiles.
; The object nearby prevents digging further down.
: An object, such as a [[bulk storage bin]] may prevent digging steep slopes.
; The water is too deep and would only dissolve the concrete.
: When using [[concrete]] to raise a tile below water the lowest height that the tile can be is 25.
==Burying==