Straightening the Leaning Tower of Pisa

On 15 December 2001, the Leaning Tower of Pisa reopened to the public after an unprecedented 11-year closure.

Famous worldwide for its dramatic lean, the tower also became, during the 1990s, the most closely monitored building on Earth. Engineers and scientists watched anxiously as the tilt worsened year by year, raising the very real possibility that the tower could topple.

The lengthy restoration effort — invisible to tourists but watched closely by experts — was a race against time, during which visitors were barred from climbing the tower for over a decade.

The complex €27 million stabilization project reduced the tower’s tilt by around 17 inches, securing the iconic structure for an estimated 200–300 years.

Nunziante Squeglia, professor of geotechnics at the University of Pisa, tells Colm Flynn about the extraordinary moment the tower reopened.

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(Photo: The Leaning Tower of Pisa. Credit: Martin Ruegner/via Getty Images)