The Tower of Pisa is known all around the world, mostly because it is characterized by the fact of being leaning. But why it is? We’ll explain it in this article.
Where to find the Tower of Pisa
Pisa is one of the most important cities of Tuscany, the fifth “comune” most populated in the region with about 90.000 people. According to ‘Italia Oggi’ and ‘Sapienza University of Rome’ 2021 research, it is the 25th city for the quality of life in Italy. The city arises only a few kilometers above the banks of Arno, the eighth-longest river of the whole Italy, just before the mouth of the river at Marina of Pisa. The history of its name is uncertain. According to several legends, the name Tuscan Pisa comes from another Pisa, in Greece, located in the regional unit of Elis, in the Peloponnesus. After the Trojan War, some habitants of this greek city founded would have built a homonymous city calling it Pisa as well.
Why the Tower of Pisa is Leaning
Building the Tower of Pisa took 199 years. The works first started on the 9th of August, 1173. According to multiple studies, the architectural project has been made by the Pisan Diotisalvi, which was building the Battistero di San Giovanni, also in Pisa, in the same years. But also about this information, there are different points of view. Others, in fact, named Gherardi or Bonanno Pisano as the real author of the Tower. In short, also the creator is pretty uncertain.
During its building, the Tower had different problems. At the half of the third floor, works were stopped after a cave-in of part of the structure. It happened because the so-called “pancone” under the Piazza dei Miracoli (aka Piazza del Duomo), where the tower is situated, has a clay floor characterized by plastic behavior (known as “normalconsolidata”) that collapsed.
It took 100 years for works to be resumed. In 1275, Giovanni di Simone and Giovanni Pisano tried to straighten the building adding three more floors in the opposite verse of the tower incline.
During centuries, the inclination continue to increase. In the 17th century, it was discovered that the field under the tower was full of water. To solve this problem, it was decided to sucked the water, a choice that brought bad effect. In fact it created another collapse which increased the inclination of the Tower. The danger of a Tower falling seems to be more concrete. Today there’s not any kind of risk, as it was decided to put a lead counterweight of 900 ton and a stabilization of the field that, according to the experts, will allow the Tower to be safe for at least three centuries.
How much the Tower of Pisa is Leaning
The Tower of Pisa is leaning 3.97 degrees, but by 1990, the tilt had reached 5.5 degrees.
It is not the more leaning tower in the world: according to Guinness Book of World Records, a 650-year-old church tower in northwest Germany is officially the most inclined building in the world.