Spacious, two-storied, with a double line of columns, the stoa (portico) of Attalus was a commercial building, of the kind found in every Greek city. Perfectly restored by the American School of Classical Studies, it gives us an excellent idea of how well they suited the local climate. Even today, the building is naturally air-conditioned and is a cool haven for visitors exhausted by the hot summer sun.
Notice how the lower part of the columns is not fluted (ie. the grooves are not finished) in order to protect the columns form the heavy loads that would have been carried. Let your imagination picture a colorful crowd browsing the shops while hawkers fill the air with cries advertising their wares.