The monument, one of the most recognizable symbols of Italy, is famous around the world due to its unintended tilt. The tilt was caused by an inadequate foundation on a ground too soft to properly support the structure’s weight.
The building of the tower began on August 9, 1173. Some recent studies attribute the project to the Pisan architect Diotisalvi, who at the time was also building the Baptistery of San Giovanni.
The first phase of the works was interrupted in the middle of the third floor, due to the subsidence of the land on which the bell-tower was built. The softness of the soil, made up of soft clay, is the cause of the tower’s tilt and, although to a lesser extent, of all the buildings in the square.
The works were resumed in 1275 under the guidance of Giovanni di Simone and Giovanni Pisano, who added another three floors to the previous structure. In an attempt to straighten the tower, the three new floors tend to curve in the opposite direction of the tilt. The bell tower was completed in the middle of the 14th century, with the addition of the belfry.
During the 19th century, the bell tower was restored under the direction of Alessandro Gherardesca.
In the last decades of the 20th century, the inclination of the tower increased, so much that the danger of collapse become imminent. During the consolidation works, started in 1990 and finished at the end of 2001, the tilt of the bell tower was reduced by removing 38 cubic meters of soil from underneath the raised end and adding lead counterweights of about 900 tons. Furthermore, the base was consolidated so that, according to the experts, it will allow the tower to be stable for at least another three centuries.
The tower has a height of 57 meters (58.36 meters, considering the foundation) and a mass of 14,453 tons. The inclination of the structure measures now 3.9 degrees from the vertical axis.
The bell-tower structure incorporates two rooms. One at the base of the tower, known as the Sala del Pesce (Fish Hall), due to a bas-relief depicting a fish. The other one is the belfry, at the seventh floor.
TIP: If you want to visit the tower without spending your precious time in the waiting line (which, by the way, is always there), buy your skip-the-line ticket in advance, to ensure you have a fast track access.
HOW TO GET THERE
The Leaning Tower of Pisa is located about 1.8 kilometers away from the Pisa Centrale railway station, or about 25 minutes on foot. The closest bus stop is in Via Contessa Matilde 62, about 250 meters away, on the bus Lines 21 and Navetta E.