An Analysis of the San Macro Bell Tower's Foundation Failure and Solutions

https://www.constructioncost.co/bell-towers-foundation-failure.html

Venetians know it as the San Marco Bell Tower, which is the tallest human made structure in the city which was made around 800 years ago. The tower is located in Piazza Public Square, one of the city's most important symbols. Later, it was discovered that the foundation masonry block was separating from its older counterpart. Accordingly, the committee recommended reinforcing the foundation a second time in order to reduce the chance that another failure would occur.