The Leaning Tower of Pisa is not only a landmark building in Italy, but also one of the wonders in the history of world architecture. The tower is actually a free-standing bell tower of the Cathedral of Pisa, located in the central square of Pisa: the Miracle Square. The building has a cylindrical shape and is made of white marble. The bottom of the tower is engraved with reliefs and on the top there is a bell pavilion. It is said that the Leaning Tower of Pisa is built with spoils transported by six ships by the Pisa fleet. The tower is tilted to the southeast, and many people believe this is due to an uneven foundation and soft soils.