The Leaning Tower of Pisa Has Gotten a Little Straighter
Engineers announced that the famed structure’s tilt has reduced by about 1.5 inches
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Since the early days of its construction, the Leaning Tower of Pisa has been plagued by its now-characteristic tilt. Work began on the bell tower in 1172; by the time builders reached the second floor, the building had started to lean. In more recent years, experts worried that the tower would topple over entirely. But as the Agence France-Presse reports, Italian engineers recently announced that the Leaning Tower of Pisa is not only in good structural health, but is also leaning a little less.
Nunziante Squeglia, an engineering professor at the University of Pisa and a member of the committee that monitors the tower, revealed that the famed structure has straightened by four centimeters (about 1.5 inches). He added that the good news is the result of a lengthy conservation effort that spanned from 1990 to 2001, during which time the tower was closed to visitors.
“We knew those measures would have protracted consequences,” Squeglia said, according to Elisabetta Povoledo of the New York Times. Engineers did not predict, however, that the structure would reduce its tilt.
The Leaning Tower of Pisa is part of a cathedral complex known as “Il Campo dei Miracoli,” or the “Field of Miracles.” The structure slumps because it was built on soft, shifting ground. Due to interruptions caused by conflict, financial setbacks and structural issues, it took nearly 200 years for the tower to be completed, which was in fact quite fortuitous. If the soil beneath the tower had not had time to compress, the entire building would have likely collapsed.
Still, the tower wasn’t in great shape. Over the centuries, it continued to slump until its tilt reached nearly 15 feet from the vertical. Experts worried it would collapse “at any moment.”
The conservation project that took place more than two decades ago saw workers put hundreds of tons of lead counterweights at the base of the tower and remove soil from its foundations, reports the Associated Press. In 2008, the engineers announced that the building had stopped moving for the first time in its 800-year history, and that the tower was 19 inches straighter as a result of efforts to salvage it.
To make sure that it continues its upward trajectory, the tower is carefully monitored and the number of visitors allowed inside the building is capped. But the site’s iconic lean isn’t going anywhere quickly. Squeglia said it would take “around 4,000 years” for the tilt to straighten entirely, according to the Times’ Povoledo, leaving plenty of time for tourists to take the obligatory “straightening the Leaning Tower” photo.