The Areopagus or Areios Pagos (Greek Άρειος Πάγος) is the 'Hill of Ares', north-west of the Acropolis, which in classical times functioned as the high Court of Appeal for criminal and civil cases in Athens. Ares was supposed to have been tried here by the gods for the murder of Poseidon's son Alirrothios. In The Eumenides of Aeschylus (458 BC), the Areopagus is the site of the trial of Orestes for killing his mother (Clytemnestra) and her lover (Aegisthus).
The origin of its name is not clear. In Greek pagos means big piece of rock. Areios could have come from Ares or from the Erinyes, as on its foot was erected a temple dedicated to the Erinyes where murderers used to find shelter so as not to face the consequences of their actions. Later, the Romans referred to the rocky hill as "Mars Hill," after Mars, the Roman God of War. Near the Areopagus was also constructed the basilica of Dionysius Areopagites.
In pre-classical times (before the 5th century BC), the Areopagus was the council of elders of the city, similar to the Roman Senate. Like the Senate, its membership was restricted to those who had held high public office, in this case that of Archon. In 462 BC, Ephialtes put through reforms which deprived the Areopagus of almost all its functions except that of a murder tribunal in favour of Heliaia.
The Areopagus, like most city-state institutions, continued to function in Roman times, and it was from this location, drawing from the potential significance of the Athenian temple to the Unknown God, that the Apostle Paul is said to have delivered the famous speech, 'Now what you worship as something unknown I am going to proclaim to you. The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands.'
The term "Areopagus" also refers to the judicial body of aristocratic origin, the power of which was enhanced by Solon, or the higher court of modern Greece.