The history of the Leaning Tower of Pisa

The Tower of Pisa is one of the most famous monuments in the world thanks to its unique inclination. It is none other than the bell tower of the Cathedral of Pisa and its construction began in 1173. In the middle of the works the tower tilted and its construction was interrupted until 1272. After which another three floors were added to the structure up to finish the work around the middle of 1300 with the completion of the belfry. According to Vasari, the tower assumed this famous position because the architects of the time did not correctly lay the foundations of the building. In this historic bell tower, Galileo Galilei carried out the experiment of the Fall of the Graves by making three spheres fall from the top of it to demonstrate that the acceleration of gravity is independent of the material they were made of. Over the years, the slope of the tower increased to reach 5.5 degrees in 1993. To avoid the collapse of the structure then work was done to give it more stability by decreasing the slope by 0.5 degrees.