The Piazza del Duomo ("Cathedral Square") is a wide, walled area at the heart of the city of Pisa, Tuscany, Italy, recognized as one of the main centers for medieval art in the world.
Partly paved and partly grassed, it is dominated by four great religious edifices: the Duomo, the Leaning Tower (the cathedral's campanile), the Baptistry and the Camposanto. It is otherwise known as Piazza dei Miracoli ("Square of Miracles").
This name was created by the Italian writer and poet Gabriele d'Annunzio who, in his novel Forse che si forse che no (1910) described the square in this way: L’Ardea roteò nel cielo di Cristo, sul prato dei Miracoli. which means: "The Ardea rotated over the sky of Christ, over the meadow of Miracles."
See more at Wikipedia - http://en.wikipedia.org/wiki/Piazza_dei_Miracoli