The iconic Leaning Tower of Pisa leaned “too far,” which resulted in its closure.

In 1990 the tower was closed and all the bells silenced as engineers undertook a major straightening project. Earth was siphoned from underneath the foundations, decreasing the lean by 17 inches (44 cm) to 13.5 feet (4.1 metres); the work was completed in May 2001, and it was reopened to the public on December 15, 2001.

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