Quelle:
http://torre.duomo.pisa.it/index_eng.html

The measurements of the Tower

The Tower is 58.36 metres high from the foundation and 55 from the ground. 
Its weight has been calculated at 14,453 tonnes. 
The centre of gravity is 22.6 metres above the foundation, which has an exterior 
dimension of 19.58 metres, with a central aperture of 4.5 metres. 
The area of the annular foundation is thus 285m2, and the average pressure on the ground 
is 497 kPa. The present inclination is about 55j - i.e. about 10%; the value 
corresponding to the eccentricity on the loads on the foundation is 2.3 metres.