Work began in Venice this week to fit a titanium belt to one of the city's most famous landmarks, the bell-tower in St Mark's Square.
Experts were called in after a survey revealed the 99-metre bell-tower is sloping by seven centimetres, a sign that its foundations - thousands of wooden posts driven into unstable ground - are failing to provide adequate support.
Surveyors also reckon the foundations of the tower are cracking by a millimetre a year.
To prevent the tower from toppling over, the titanium belt will be wrapped around its foundations two metres below ground and will be invisible from the outside.
Consorzio Venezia Nuova (CVN), the conservation group in charge of the restoration, has warned that the picturesque square - a must on Italy's tourist trail - will be covered in scaffolding for the next two years while the belt is fitted.