Piazza S.Marco is the only true square in Venice (the others open areas are campi ). St.Mark's Square was called "the drawing room of the world" by Musset. It has been the scene of some of the most important religious and political activities of the Serenissima as well as the center of Venetian social life for almost a millennium. At first the Square was limited to the parvis of the Basilica, because of the presence of a canal, "Rio Batario", which divided the present Square in two parts. The part of the Square now between the Procuratie, was once the vegetable garden of S.Zaccaria monastery with S.Geminiano church in the middle. The present shape of the Square was established in the XII century, for the meeting of Pope Alexander III and the Emperor Barbarossa by filling in Rio Batario and the dock. A small new Square was built with the columns of S.Marco and S.Todaro, the city's patron saints, overlooking St. Mark's Basin. The alteration of the Square was all done over the course of one century, adapting to the growing power and wealth of Venice. The present form reflects the works of many famous architects such as Sansovino, Longhena, Scamozzi, Rizzo and Tirani.