The Leaning tower of Pisa is one of the most amazing structures in the world. Located in the city of Pisa , Italy , it is visited by hundreds of people every day. Very few people know the reason of its leaning. Made of whit marble, this structure has walls 4 meters thick at its base. It has 8 floors and is 54.5 meters high and measures 15.8 meters round the bases. There is a stairway, which leads to the top and has 300 steps. From its top, it is possible to get a breath taking view of the city and the sea, which is 10 kilometers away.

The Leaning Tower of Pisa

Now the question arises- what makes this tower lawn and why does it not fall? Plumb line form the top is meters away from the base, i.e. it leans over by 4 meters. If we drop a ball from its top, it would hit the ground 4 meters away from its base.

Originally, it was intended as a bell tower for the cathedral, which is nearby. Its construction was started in 1174 A.D. and completed in 1350 A.D. when the construction started no body though that it would lean, but it started leaning as soon as the third storey was completed. The foundation of the tower was laid in sand and this may explain why it leans. Since the tower started leaning, the plan for its construction was modified and then the tower was completed.

Since 1918, yearly measurements have been made. These measurements show that the leaning is increasing. During the last one hundred years the tower has leaned another 30 centimeters.

But why does it not fall even while leaning? According to science, anything will remain stable as long as the vertical line drawn from the centre of gravity passes through it base. The centre of gravity is that point where the whole mass of the body is supposed to be concentrated. Till today the vertical line from the centre of gravity has bee falling within the base of this tower. That is why it has not fallen. It is believed that when the tower leans further and the line from its centre of gravity passes out of its base, it will fall down.

However, by using different new methods and techniques, engineers and technologists are now trying to arrest further leaning of the tower.