The Tower of Pisa (Torre pendente di Pisa in Italian), a symbol of central Italy and emblem of the Tuscan city of Pisa, is the bell tower of Pisa’s Cathedral, in Piazza dei Miracoli ( Place Miracles ) and whose construction began in 1173.

His fame comes from its particular characteristic inclination (which is currently at an angle of 3.99 ° south), appeared very quickly during its construction, to the fact that it was built on an alluvial plain. This defect was due either to a lack of foundation, or land subsidence of a rock: the marl.