Pisa's leaning tower safe for 300 years: expert

During the stabilization phase of the project which ended in 2001 the structure was anchored to cables while cement was injected to relieve pressure on the ground. The lean of the tower is now considered safe and is about what it was in 1700.

Restorers are now using a specially-designed, light-weight scaffolding made of an aluminum alloy as a base from which to clean the tower's white and grey marble.

Officials have said over the years that they have no intention of straightening the tower, which would detract from its unique status and tourist draw.

Astronomer Galileo, who was hauled before the Vatican's Inquisition for his view that the earth revolved around the sun, is said to have used the tower of his hometown for experiments on gravity.

(Reporting by Philip Pullella)