A cave with an essentially horizontal network of interconnecting and mainly contemporaneous passage loops. Three broad types of maze cave have been described - anastomotic, network and spongework - and these may be subdivided on the basis of how they developed by slow-moving water, restricted to a confined, artesian aquifer, or by water that is ponded due to backflooding. A mechanism of potentially great importance, particularly in the context of the inception of network maze caves, is multiple, diffuse input from adjacent, permeable but noncavernous rocks. Spectacular jointguided maze caves such as Knock Fell Caverns and the Devis Hole Mine Caverns occur in the thin Yoredale limestones of the northern Pennines, but the most extensive mazes are in the Black Hills of Dakota, USA (including Jewel Cave) and in the Ukrainian gypsum karst (including Optimisticeskaja) . See also maze cave pattern.