Closure due to safety concerns

For eleven years, the Leaning Tower of Pisa remained closed to the public, considered too dangerous to accommodate any visitors. The closure followed years of concern about its stability and the risk of collapse.

Engineering goal defined by a number

Engineers did not attempt to fully straighten the tower. Their goal was to reduce its tilt by 45 centimeters, no more, to restore its position to what it was in 1838. This specific target aimed to preserve the tower's visual identity while ensuring its structural safety.

Soil removal under the foundations

Between 1999 and 2001, approximately 38 cubic meters of soil were removed from beneath the northern side of the foundations to stabilize the tower. This method, directed by engineer John Burland, successfully reduced the tilt without fully straightening the monument.

Careful early stages of the project

The stabilization works officially began in February 1999. The first soil extraction took place under the foundations on February 9, marking the true beginning of the operation after years of theoretical preparation. Initial work was done with extreme caution, using small boreholes to test the tower's response.

Progress and completion of the project

By early June 1999, the northward rotation reached approximately 80 arc seconds. After verifying the tower's stability, engineers expanded the extraction across the entire width of the foundations. The last soil extraction was completed on June 6, 2001, achieving the targeted reduction in tilt.

Preserving the tower’s identity

Fully straightening the Leaning Tower of Pisa would have been a mistake. Its tilt is part of its identity and what attracts millions of visitors. Engineers aimed to restore the tilt to its 1838 level, ensuring both safety and the preservation of the tower’s historical and visual character.

Post-reopening monitoring

The tower reopened to the public in December 2001, after eleven years of closure. Since then, sensors have continued to monitor every movement of the monument. The Leaning Tower of Pisa remains tilted but stands upright due to the precise soil removal that allowed it to lean slightly less, preserving its iconic appearance.