http://agathe.gr/guide/southwest_area.html
Southwest Area - Industry and Houses Leaving the area of the boundary stone, one can head southwest up a valley leading toward the Pnyx, meeting place of the Athenian assembly. Here are the complex remains ... The "Industrial District," southwest of the Agora. The Poros Building at the top (north) has been tentatively identified as the State Prison. ... One larger structure, the so-called Poros Building, has a long corridor flanked by square rooms, with a courtyard at the rear (Fig. 28). ... Figure 28. The Poros Building, possibly the State Prison, seen from the north, 5th century B.C.
