Well 12: Archaic.
It lies on a rocky ledge about thirty meters north of the Klepsydra, just east of the Panathenaic street. In spite of its depth, it produced little pottery and its contents were of slight ... 6th c. B.C.? ... In the well were not merely the usual quantities of domestic wares, pithoi, tubs and the like, of broken up terracotta rooftiles and crude brick; there was also a number of building stones: three large blocks of poros from some archaic structure, and many small carefully dressed blocks of Acropolis limestone from a polygonal wall or walls.