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Welcome to
Italia
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Outline :

Introduction .

Construction basis .

Obstacle in building.

Reservation.

History following construction.

Technical information.
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1, Introduction

The leaning tower of Pisa is a campanile or a freestanding bell tower.
It is the third oldest structure in Pisa’s Cathedral.
It was built to show the wealth of the city of Pisa.
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The Pisa was performed in three stages over a period of 177 years, beginning on August 9, 1173.
In 1198, clocks were installed on the third floor.
1372: adding bell-chamber.
There are seven bells.
It was built by Tommaso .

2, Construction basis:
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3, Obstacle in building:

The tower began to sink after construction had progressed to the third floor in 1178.
=>Cause: _ mere three-metre foundation.
_ weak, unstable subsoil.
In 1272, the tower was actually curved.
In 1284, Construction stopped again.

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4, Preservation:
On February 27, 1964, the government of Italy requested aid in preventing the tower from toppling.
Many methods were proposed to stabilize the tower .
In 1987, the tower was declared as part of the Piazza del Duomo UNESCO World Heritage Site
On January 7, 1990, the tower was closed to the public.
On December 15, 2001, the tower was reopened to the public and has been declared stable for at least another 300 years.
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5, History following construction:
Galileo Galilei: The speed of descent was independent of mass.



During World war II: Pisa was used as an observation post .
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Elevation of Piazza del Duomo: about 2 metres.
Height from the ground floor: 55.863 metres, 8 stories.
Height from the foundation floor: 58.36 metres.
Outer diameter of base: 15.484 metres.
Inner diameter of base: 7.368 metres.
Angle of slant: 3.97 degrees or 3.9 m from the vertical.
Weight: 14,700 metric tons.
Thickness of walls at the base: 2.4 m.
Total number of bells: 7, tuned to musical scale, clockwise.
Number of steps to the top: 296.
6, Technical information:
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