Pisa was born as an Etruscan port, around the middle of the VI century. Etruscans called the city Pise and developed the economy of the country through the production arts and crafts. The city had a strategic position, being close to river Arno and the sea. The Piazza del Duomo ("Cathedral Square"), known with this name in the past, is also called Piazza dei Miracoli ("Square of Miracles"). This name was created by the poet Gabriele D'Annunzio, who by observing it from above on a plane, called it "Prato dei Miracoli" (Meadow of Miracles), because of the beauty of the marble monuments, which looms within the surrounding green garden. The square lies at a Northern area of the city, that once was a graveyard and the place of an Early Christian cathedral. Differently from other cities, Pisa's Cathedral Square is not inside the walls nor in the old town. The Duomo was the first monument to be built, followed by the construction of the Baptistery and of the Leaning Tower (the famous Pisa's Tower). Two sides of the square (which represent the Northern and Western parts) are included in the walls that dating back to 1154.