Authorities in northern Italy have taken immediate action to secure the Garisenda Tower, a historic medieval structure that has shown signs of impending collapse. The city's council has deemed the situation "highly critical," prompting the construction of a 16ft barrier around the tower to collect potential debris.

The 154ft tower, standing proudly for 900 years, has long been an iconic feature of the Bologna skyline. However, recent monitoring by the University of Bologna has raised concerns about its stability. While the tower usually leans at a four-degree angle, noticeable shifts in its inclination have been recorded.

Experts had previously warned about the possibility of the tower's weak foundations subsiding, which may necessitate injecting filler material to reinforce its stability. Additionally, abnormal noises, oscillations, vibrations, and small movements within the tower were detected by the city's tourist board, further intensifying worries.

The site around the Garisenda Tower was closed off two months ago when sensors first detected changes in its tilt. This precautionary measure aimed to ensure the safety of the public in case of a sudden collapse.

Both the Garisenda Tower and the neighboring Asinelli Tower were constructed between 1109 and 1119, showcasing the historical significance of Bologna. These towers played a crucial role in the city's rapid expansion, becoming an integral part of its prosperous commercial hub in northern Italy.

While the Asinelli Tower still welcomes visitors to climb its sturdy structure, the potential loss of the Garisenda Tower would be a devastating blow to the city's rich history. The city's tourist board highlighted the cultural importance of preserving the smaller tower, stating that its hypothetical loss would be "tragic" for both tourism in Bologna and Italy's historical legacy.

In response to the critical situation, Lucia Borgonzoni, the Italian culture undersecretary, announced that the government would allocate approximately €5 million (£4.3m) from Italy's EU national recovery fund to reinforce the tower. This funding aims to ensure the preservation of this architectural gem.

The Garisenda Tower's lean, like several other medieval towers in Bologna, is attributed to the soft ground and the base materials used in its construction. Made of mortar terracotta bricks and river stones, the base material has gradually sunk into the city's soil, resulting in the tower's distinctive tilt.

While the structural issues faced by the Garisenda Tower are similar to those of the renowned leaning tower of Pisa, experts estimate that the latter could remain stable for another two centuries.

Efforts to secure and preserve the Garisenda Tower are underway, as authorities recognize the need to safeguard this cultural gem from potential collapse. As tourists and locals eagerly await its restoration, experts will continue their diligent work to retain the tower's historical significance for generations to come.