How has the Tower of Pisa been leaning for years?

The tower of Pisa has been leaning so long -- nearly 840 years -- that it's natural to assume it will defy gravity forever. But the famous structure has been in danger of collapsing almost since its first brick was laid. It began leaning shortly after construction began in 1173. read more

There has been controversy about the real identity of the architect of the Leaning Tower of Pisa. For many years, the design was attributed to Guglielmo and Bonanno Pisano, a well-known 12th-century resident artist of Pisa, famous for his bronze casting, particularly in the Pisa Duomo. read more

The Tower of Pisa has been leaning for more than 800 years, but it has never fallen. read more

The straightening continued after the tower reopened in 2001, and in 2008 sensors showed the subsiding motion had stopped, after a total improvement of some 19 inches. Engineers now believe the Leaning Tower of Pisa will remain stable for some 200 years, barring an earthquake or other unpredictable disaster. read more