The Leaning Tower of Pisa is the cathedral of the Cathedral in Pisa, Italy. In the same area is the cathedral and the cemetery.
The slope of the building began with the start of construction work. This is because there was insufficient foundation at its base. Over the centuries the slope has increased. However, with the corrective work carried out from 1990 to 2001, the slope was reduced from 5.5 degrees to 3.97.
Construction began in 1173 AD. In 1178 work stopped for almost a century. Its architect is not clear who he was. Maybe it was Pisano or Diotisalvi.
Its construction materials were mainly stone and marble.
It has a height of 55.86 meters and a diameter of 15.48. Its weight is estimated at 14,450 tons. It has seven bells, one for each note of the musical scale.
It has been a UNESCO World Heritage Site since 1987.
[Source: el.wikipedia.org]
