The Garisenda tower in Bologna, Italy, famously known for its leaning stature, has stood tall for almost a millennium. However, its days may be numbered as the city of Bologna initiates a civil protection plan for the "sudden and unexpected collapse of the tower." The city council has announced that a protective metal cordon will be erected around the tower to contain any debris in case of a collapse. Specially designed rockfall protection nets will also be included in the cordon to minimize the vulnerability of surrounding buildings and protect the population.
A comprehensive 27-page report, shared with CNN, from the scientific committee responsible for monitoring the tower since 2019 has put the site on high alert. According to the report, there has been an unexpected and accelerated trend of compression towards the tower's base, causing the stone cladding to disintegrate and cracks to expand in the upper brickwork. As a result, the ongoing consolidation works have been halted, and an exclusion zone will be established as quickly as possible.
However, despite the precautions taken, the tower is not on the brink of immediate collapse. A spokesperson clarified that they are treating the situation as if it were the worst-case scenario, but the exact timing of a potential collapse remains uncertain. The monitoring equipment provides readings every 15 minutes, ensuring that they would have early warning if a collapse were imminent, allowing them to evacuate the surrounding area promptly.
The Garisenda tower is one of Bologna's famous "twin towers" that have long dominated the city's center. Originally constructed in the 12th century, these towers symbolize Bologna's past when numerous towers dotted the skyline, built by local families competing to erect the tallest structure. Today, only a few towers remain, many of which have been modified into regular houses. The Garisenda tower leans at an angle of four degrees, slightly less than the famous Leaning Tower of Pisa's five-degree tilt. It has captivated the imagination for centuries, even inspiring Dante's description of the tower's leaning side in "Inferno."
In October, Bologna's mayor, Matteo Lepore, ordered the area around the twin towers to be blocked off for research purposes. Various sensors were deployed to monitor cracking and creaking noises, and pendulums were installed to track any excessive oscillations. Unfortunately, the recent research has revealed both increased compression in the tower's base and a shift in its leaning direction by 90 degrees.
The tower's condition has gradually deteriorated since July, according to the city council spokesperson. The report explicitly states that the tower has been in an "inescapably critical condition for some time." Moreover, prior intervention attempts, such as steel rods and cables placed around the tower's base in 2020, seem to have aggravated the situation. Extreme weather events, including high temperatures this summer and earlier flooding, have also likely played a role in the deterioration.
To protect the public and surrounding structures, the city council plans to complete the construction of the protective cordon by February. However, renderings of the cordon reveal bright red barriers, deviating from the medieval aesthetic of the surrounding buildings. Nevertheless, the council ensures that any anti-collapse measures taken will be reversible.
Following the installation of the cordon, research will be conducted in two phases: stabilizing the tower and addressing the underlying problem causing its deterioration. The first phase may involve creating a metal "cage" structure, while the proposed solutions for the second phase range from dismantling and rebuilding the base to trimming the tower, as was done in medieval times. The council spokesperson admitted that there are no set rules for such a unique, nearly 1,000-year-old structure.
However, the repair works will come at a significant cost. The cordon alone is estimated to cost 4.4 million euros (about $4.8 million), and stabilizing the tower will require millions more. To fund these efforts, the council has launched an online fundraiser, which has already gathered 800,000 euros within a week. The spokesperson emphasized the symbolic and cultural importance of the twin towers, along with the city's UNESCO-protected porticoes, stating that preserving them extends beyond heritage conservation—it serves as a powerful symbol for the city of Bologna.