The Stoa was a common building type found throughout ancient Athens.  It consisted of two rows of columns supporting a roof with a wall on one side (click here for a plan of a stoa from the Perseus Project).  Stoas were both ornamental and practical.  They served as promenades sheltered from the heat of summer and the cold winds of winter, as judicial and shopping centers, and as boundary markers.  For example, the Agora was bounded by the Stoas of the King Archon (Stoa Basileios) and Zeus Eleutherios on the west, the South Stoa on the south, and in the second century BC, the Stoa of Attalus (see below) on the east.
 
 

Attalus II, the king of Pergamum (159-138 BC), gave this Stoa to the Athenian people as a gift in return for the education he had received at Athens.  This stoa was a monumental building, much greater in size than any of the earlier-built stoas mentioned above.  It consisted of two stories and behind the double colonnades  was an enclosed area  housing 21 shops on each story.  The Stoa seen in this picture is a modern reconstruction (1953-56) and now houses the Agora Museum rather than shops, as in ancient times.
 
 

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