The Leaning Tower of Pisa is famous for its tilt — but did you know it was once on the verge of collapse? This video explains ...

The Leaning Tower of Pisa is a true marvel of engineering. It draws many visitors who want to learn about its secrets. Its ...

Two unidentified Chinese tourists pretend to hold up the leaning tower of Pisa, in central Italy, the day before the official opening ceremony marking the end of restoration on Friday, June 15, 2001.

The Leaning Tower of Pisa in Italy sure doesn't look like it should still be standing. The defiant 500-year-old architectural wonder should have been taken down by a major earthquake by now.

The Tower of Pisa was once feared on the brink of collapse as the lean that made it such a popular landmark threatened its very existence. As it celebrates its 850th birthday, experts now say its ...

The Leaning Tower of Pisa (Torre di Pisa) is seen at right next to the medieval cathedral of Pisa, in Piazza dei Miracoli Square, in Pisa, Italy, Sunday, Jan. 2, 2012.

Oh, the Leaning Tower of Pisa — so touristy and yet so fun. Each day, hordes of visitors come to the small northwestern Tuscan town of Pisa to take pictures "propping up" its tower.

In fact, as well as the Leaning Tower of Burnham, the town also has a bizarre collection of lighthouses. It's picturesque nine-legged 30ft-high wooden one was built in 1832 on offshore tidal flats.

The Tower of Pisa was once feared on the brink of collapse as the lean that made it such a popular landmark threatened its very existence. As it celebrates its 850th birthday, experts now say its ...