The Areopagus is the small marble outcrop just west of the Acropolis, a few minutes' walk from the entrance ramp. It was the meeting place of the oldest council of Athens — the Areopagites, an aristocratic body that judged homicide cases and (for a time) supervised the constitution.
For most visitors today it is the viewpoint where you sit after coming down from the Acropolis. The rock is climbable by a set of worn marble steps cut directly into the stone — slippery in any weather — and the platform on top gives one of the best free views over the Plaka, the Ancient Agora, and the surrounding hills. Best in the late afternoon, when the light turns the Acropolis honey-gold.