Leaning Tower of Pisa, Italy, is the most famous leaning tower in the world. It is a campanile, or bell tower, of the Cathedral of Pisa in Italy.
The Leaning Tower is situated behind the Cathedral of Pisa, and is the third oldest structure in Pisa's Piazza del Duomo (Cathedral Square) after the cathedral itself and the baptistry.
The tilt of the tower is its call to fame. Although intended to stand vertically, the tower began leaning to the southeast soon after the onset of construction in 1173. This is due to a poorly laid foundation and loose substrate that has allowed the foundation to shift direction. The tower presently leans to the southwest.
Leaning Tower of Pisa
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The Leaning Tower of Pisa is part of the Piazza del Duomo (Cathedral Square) of Pisa, which was inscribed as a World Heritage Site during the 11th session of the World Heritage Committee meeting in Headquarters in Paris, France, on 7-11 December, 1987.
World Heritage Site Inscription Details
Location: N 43 43 23 E 10 23 47 in Pisa, Tuscany, Italy
Inscription Year: 1987, with modifications in 2007
Type of Site: Cultural
Inscription Criteria: I, II, IV, VI
Dimensions of the Leaning Tower
The height of the Leaning Tower of Pisa is 55.86 m (183.27 ft) from the ground on the lowest side and 56.70 m (186.02 ft) on the highest side. The width of the walls at the base is 4.09 m (13.42 ft) and at the top 2.48 m (8.14 ft).
The weight of the Leaning Tower is estimated at 14,500 metric tons (16,000 short tons). The tower has 296 or 294 steps; the seventh floor has two fewer steps on the north-facing staircase. The tower leaned at an angle of 5.5 degrees, but after the restoration works between 1990 and 2001 it now leans at an angle of 3.99 degrees. This means that the top of the tower is 3.9 metres (12 ft 10 in) from where it would stand if the tower were perfectly vertical.
Leaning Tower of Pisa
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Construction of the Tower of Pisa
The Tower of Pisa was built in three stages over a period of about 177 years. Construction of the first floor began on August 9, 1173, a period of military success and prosperity. This first floor is surrounded by pillars with classical capitals, leaning against blind arches.
The tower began to tilt after construction reached the third floor in 1178. This was the result of a foundation that was just three meters deep set in weak, unstable subsoil. In other words, the design was flawed from the beginning.
Construction stopped for almost a century, because the Pisans were almost continually engaged in battles with Genoa, Lucca and Florence. This allowed time for the underlying soil to settle. If not, the tower would definitely have toppled over.
In 1198, clocks were temporarily installed on the third floor of the unfinished construction. Construction resumed in 1272 under Giovanni di Simone, architect of the Camposanto.
In an effort to compensate for the tilt, the engineers built higher floors with one side taller than the other. This made the tower begin to lean in the other direction. Because of this, the tower is actually curved. The defeat of Pisa to Genoa in 1284 in the Battle of Meloria brought construction to a stop once more.
Map of the Leaning Tower of Pisa
View Leaning Tower of Pisa in a larger map
The seventh floor was completed in 1319. Many more years were to pass before the bell-chamber was finally added in 1372. It was built by Tommaso di Andrea Pisano, who succeeded in harmonizing the Gothic elements of the bell-chamber with the Romanesque style of the tower. There are seven bells, one for each note of the musical major scale. The largest one was installed in 1655.
After a phase (1990-2001) of structural strengthening, the tower is currently undergoing gradual surface restoration, in order to repair visual damage, mostly corrosion and blackening. These are particularly strong due to the tower's age and to its particular conditions with respect to wind and rain.
On January 7, 1990, after over two decades of work on the subject, the tower had to be closed to the public. During this period, the bells were removed to relieve some weight. Cables were cinched around the third level and anchored several hundred meters away. Apartments and houses in the path of the tower were vacated for safety.
The final solution to prevent the collapse of the tower was to slightly straighten the tower to a safer angle. This is done by removing 38 cubic metres (50 cu yd) of soil from underneath the raised end.
The tower was straightened by 18 inches (45 centimetres), returning it to the exact position that it occupied in 1838. After a decade of corrective reconstruction and stabilization efforts, the tower was reopened to the public on December 15, 2001, and has been declared stable for at least another 300 years.
In May 2008, after the removal of another 70 metric tons (77 short tons) of earth, engineers announced that the Tower had been stabilized such that it had stopped moving for the first time in its history. They stated it would be stable for at least 200 years.
Meanwhile, two German churches, the 15th century square Leaning Tower of Suurhusen and the nearby 14th century bell tower in the town of Bad Frankenhausen, have challenged the tower's status as the world's most lop-sided building. Guinness World Records measured the Pisa and Suurhusen towers, finding the former's tilt to be 3.97 degrees.
Visiting Leaning Tower of Pisa
The Leaning Tower of Pisa is located in the city of Pisa, a city in Tuscany, Italy. There are regular trains to Pisa from Florence, three every hour, and from Lucca, every hour. The Pisa Galileo Galilei Airport is the main airport for Tuscany. It is served by several airlines.
Getting around in Pisa
There are buses that you can take to go to the Piazza dei Miracoli, or Field of Miracles, where the Leaning Tower of Pisa is located. Taxis will be expensive, but if you intend to explore, you should rent a car and drive around.