The cathedral in Pisa has a free-standing bell tower on which construction began August 9, 1173 and took 117 years to complete. The development of the Tower started in 1173. Initially intended to be a bell tower, it stood upright for more than 5 years, yet when the third floor was finished in 1178 it started to lean. Built on a small foundation in soft soil, however, the massive tower soon began to tilt and over the centuries came to be know as the Leaning Tower of Pisa. Through the centuries many plans were devised to correct the tilt, but none were ever determined to be feasible given the size of the massive structure.

In 1987, the Leaning Tower of Pisa became a UNESCO World Heritage site. By 1990, however, engineers determined that the increasing tilt was a danger to visitors and on January 7, 1990 the Leaning Tower of Pisa was closed to the public. Engineers removed the bells from the tower to decrease the weight and stress on the building. By removing soil from the raised side of the Tower, a correction of 18 inches was achieved. During restoration work performed between 1990 and 2001, the north-side establishments were dug out and the tilt was decreased by half a degree. In 2008, researchers reported the movement had at last halted and the Leaning Tower, presently tilted at 3.9 degrees, is supposed to stay put for next 200 years.

The Leaning Tower tower was re-opened to the public on December 15, 2001. Climbing to the top of the Leaning tower of Pisa is a unique experience and it offers a very beautiful view of the town.