The Stoa, on the east side of the Ancient Agora, was the gift of Attalos II, King of Pergamon, as a fragmentary inscription on the epistyle of its lower colonnade shows:

«King Attalos, son of Attalos and of Queen Apollonis».

The building is 120 m wide and 20 m deep and had two floors with a second series of columns on the interior and 21 shops at the back of both floors. On the ground floor the exterior colonnade was Doric and the interior Ionic, without fluting. On the upper floor the exterior colonnade was Ionic, and the interior had capitals of a Pergamene type. The Stoa of Attalos was a place for Athenians to meet, walk, and to do business. It was destroyed by the Heruli in A.D. 267, and its members were incorporated into the Late Roman Wall. The restoration, based on studies by the architect Yannis Travlos, was carried out in 1953-1956 by the American School of Classical Studies, with the financial support of John D. Rockefeller, Jr.