It is located 40m.inside a natural cleft, which created when a large section of the Acropolis rock came apart. It could be entered only by means of a hidden and guarded stairway, which extended from the northwest corner of the House of the Arrephoroi to the Acropolis. The stairway, in the cleft, consisted of eight sections. The two at the top, which led into a cavelike opening on the North Slope, had wooden steps set into the rock, while the others were constructed of stone slabs. At the end of the eighth section there is a well-like cut in the rock, 8m. deep, 2m.wide at the top and 4m. wide at the base, where was a hollow for the collection of sediment. The water was pumped by the use of pots. The pottery collected from the excavation showed that the construction of the fountain is dated in the late 13th century B.C.