Excavations
Excavations at the site were begun in 1910 by the Greek Archaeological Society and definitely confirmed the site as the Pnyx. Large-scale excavations were conducted at various times between 1930 and 1937 by Homer Thompson, in collaboration first with K. Kourouniotes and later with Robert Scranton.
These excavations discovered the foundations of the important buildings at the Pnyx, although nothing else remains of them. These included the two large stoas, erected between 330 and 326 BC, the Altar of Zeus Agoraios, erected at the same time, but removed during the reign of Augustus (first century BC), and the Sanctuary of Zeus Hypsistos. Most of these buildings were erected after the Pnyx had lost its real significance.
West to the Altar of Zeus are the foundations of Meton's heliotropion, the oldest known astronoical observatory, where he performed several of his measurementsthat led to the calculations involving the eponymous 19-year Metonic cycle which he introduced in 432 BC into the lunisolar Attic calendar, a calendar that appears in the Antikythera Mechanism.
Today the site of the Pnyx is under the control of the Ephorate of Prehistorical and Classical Antiquities of the Greek Ministry of Culture. The surrounding parkland is fenced, but the traveler can visit it free of charge at any time during daylight.
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