San Marco Square lies at the edge of the largest and lowest island in the Venetian lagoon and is the only square in the city which is called piazza, with all the others being called campo. It has two distinct zones, yet their function may not be understood without considering the whole, which actually makes them inseparable: the square itself and the San Marco plaza, which connects to the sea through the molo, the pier. Piațeta dei Leoncini, with a side marked by the northern wall of the Basilica, opposite to San Marco square, has functioned (and still does) as a continuation of the square itself, and thus has a less palpable identity. It received its name quite late, after statues of lions, sculpted from red Cottanello marble, were brought into its centre in 1722. The initial nucleus is essentially represented by San Marco plaza, initially planned as a square and courtyard of the Doge’s Palace in a time when the spot of the current Basilica was taken only by a palace chapel. The space of the square itself appeared only after the 1156 clogging of a river which cut the actual perimeter in two, and the square became a Square only after Venice underwent a number of historical changes, the steps of a communal psychological transformation. Today it is probably the most photographed square in the world, with over 12 million tourists every year.