The Marching Springs
The narrow plain and foothills between the Fangwood and the eastern slopes of the Mindspin Mountains are home to an unusual water feature of unknown origin or cause. Sprays of water not unlike miniature geysers about 5 feet high leap up one after another in a slow-moving progression that winds its way throughout a region of roughly 30 square miles. The springs never erupt from exactly the same spot twice, and they leave no evidence that they appeared, other than a spot of wet ground. The Marching Springs spray roughly once every 3 minutes, with each advancing about 6 feet beyond the previous one.
Sources: Pathfinder Chronicles Campaign Setting