http://agathe.gr/guide/northwest_corner_and_the_hermes.html
Northwest Corner and the Hermes The area of the northwest corner is where the Panathenaic Way, leading from the main gate of Athens, the Dipylon, entered the Agora square (Figs. 58, 59). This was accordingly ... Northwest Corner and the Hermes The area of the northwest corner is where the Panathenaic Way, leading from the main gate of Athens, the Dipylon, entered the Agora square (Figs. 58, 59). This was accordingly the appropriate place for Herms, primitive markers used by the Athenians to mark all entrances. ... "Menekles or Kallikrates in his work on Athens writes, 'From the Stoa Poikile and the Stoa Basileios extend the so-called Herms.