The Leaning Tower of Pisa is a UNESCO World Heritage Site, landmark of the Italian city and a magnet for millions of tourists. Its inclination made it famous, but it also gave cause for concern. Already during the construction, the tower sank into the sandy ground, so that from the fourth floor onwards, it had to be built diagonally in order to compensate the inclination. 

Many other measures to prevent the tower from collapsing, however, worsened the inclination. It was only in the 1990s that it was possible to stabilize the tower in such a way that it was once again accessible to tourists. 

The tower's Surveillance Group – set up to monitor restoration progress – said in a statement that after 17 years of observation "the Tower of Pisa is stable and very slowly reducing its lean." Engineering Professor Nunziante Squeglia of Pisa University said that the 57-metre (186-feet) monument had straightened by four centimetres (1.5 inches), Italian media reported.

The so-called Surveillance Group was set up after Michele Jamiolkowski, an engineer of Polish origin who adopted Italian nationality, coordinated an international committee to rescue the landmark between 1993 and 2001.Since the beginning of the measures to prevent the tower from tipping over, the world-famous structure has been erected by a total of 45 centimetres, the newspaper "Corriere della Sera" reported. "It is as if the bell tower had been rejuvenated by almost two centuries," an expert quotes. 

According to calculations, the building is thus secured for the next 300 years. It is not supposed to be quite straight. Otherwise Pisa and the whole of Italy would lose one of their most famous landmarks.

is/ks (kna, afp)