TONY CRADDOCK / SCIENCE PHOTO LIBRARY TONY CRADDOCK / SCIENCE PHOTO LIBRARY
Leaning tower of Pisa. This is actually the bell tower, or campanile, of the city's cathedral. It was under construction from 1173-1372. It is 55 metres high, and has foundations only 3 metres deep in the soil. Soon after construction began the tower started to lean. Some of the upper storeys were placed off centre to try to counteract the lean. At present, the top of the tower is about 4 metres off vertical, a tilt of about 4.2 degrees, and the tower is in danger of collapse. Scientists are trying to devise a way to reduce the tilt to about 3 degrees and to stabilise the foundations.
Model release not required. Property release not required.