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Stoa of Attalos Lining the east side of the Agora square is the Stoa of Attalos (Fig. 47), built during the reign of Attalos II of Pergamon (159–138 B.C.), who studied in Athens under the philosopher Karneades ... The facetting of the lower part of the outer colonnade reflects the intense use of the building; lots of people and goods will have passed through, rubbing and banging against the columns, so there was little point in fluting them at the level of potential damage and wear.