The Pnyx (Πνύκα) is a hill in central Athens, the capital of Greece. Beginning as early as 507 BC, the ancient Athenians gathered on the Pnyx to host their popular assemblies, thus making the hill one of the earliest and most important sites in the creation of democracy. The Pnyx is located less than 1 kilometre (0.62 mi) west of the Acropolis and 1.6 km south-west of the centre of modern Athens, Syntagma Square.
The Pnyx is a small, rocky hill surrounded by parkland, with a large flat platform of eroded stone set into its side, and by steps carved on its slope. It was the meeting place of one of the world's earliest known democratic legislatures, the Athenian ekklesia (assembly), and the flat stone platform was the bema, the "stepping stone" or speakers' platform. As such, the Pnyx is the material embodiment of the principle of isēgoria (Greek: ἰσηγορία ), "equal speech", i.e. the equal right of every citizen to debate matters of policy. The other two principles of democracy were isonomia (ἰσονομία), equality under the law, and isopoliteia (ἰσοπολιτεία), equality of vote and equal opportunity to assume political office. The right of isēgoria was expressed by the presiding officer of the Pnyx assembly, who formally opened each debate with the open invitation " Tis agoreyein bouletai? " ("Who wishes to speak?").
The Pnyx was used for popular assemblies in Athens as early as 507 BC, when the reforms of Cleisthenes transferred political power to the citizenry. It was then outside the city proper, but close enough to be convenient. It looks down on the ancient Agora, which was the commercial and social centre of the city. At this site all the great political struggles of Athens of the "Golden Age" were fought out. Pericles, Aristides and Alcibiades spoke here, within sight of the Parthenon, temple of Athena. Here Demosthenes delivered his vilifications of Philip of Macedon, the famous Philippics. French classical scholar Robert Flacelière states that the Pnyx had enough standing room for as many as 20,000 citizens.
The grassy area in front of the bema was in ancient times an area of bare rock, in which about 6,000 men could stand. This can be taken as a reasonable estimate of the number of politically active citizens (citizens were free males born in the city, or perhaps 20% of the adult population). There were wooden seats for the members of the Council of 500, who were elected by the Assembly to run the city on a day-to-day basis. In later times two stoae, or covered galleries, were built to protect the dignitaries against the rain and sun. In theory, all citizens were equal and all had the right to speak. In practice Athens was a hierarchical society like any other, and those recognized as leaders tended to dominate proceedings. Many of these belonged to the old aristocratic families which had ruled Athens before the advent of democracy, but the poor and the unknown citizen could sometimes rise to prominence if he spoke well and captured the mood of the assembly. There was a rule that citizens aged over 50 had a right to be heard first.
Democratic government at Athens was suspended in 411 BC and again in 404 BC with the assumption of power by oligarchies during crises in the Peloponnesian War. The Spartans and their allies in Athens installed a dictatorship, called the Thirty Tyrants, but in 403 BC the democrats seized power again and the meetings at the Pnyx resumed. Athens lost its independence to Philip II of Macedon after the battle of Chaeronea in 338 BC; but they continued to run their internal affairs democratically until the coup by Demetrius of Phaleron in 322 BC. After his fall, the Athenians continued to run their internal affairs according to democratic forms for centuries.
The Pnyx was very important to Ancient Greeks 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.