This is about all that remains of Daiunji Temple (大雲寺), founded in 971.
In the days before modern mental health care, waterfalls and sacred water were believed to help relieve mental illness. This belief was bolstered by the miraculous cure in the 11th century of the emperor's sick daughter who came to Daiunji temple, drank the water, bathed in this waterfall (called Fudo no Taki (不動の滝), and prayed diligently to the temple's god. Hearing of this cure, people from all over Japan came to Daiunji Temple to pray and to use the water for treatment. As a result, for centuries the Iwakura area of Kyoto came to be famous as a place for the care of the mentally ill. Daiunji Temple has now almost entirely disappeared, with only a few hints here and there in the landscape of where it once stood. Ironically almost the entire temple grounds are paved over by a modern mental care facility, leaving this old waterfall at the far end of a parking lot.