The Seventy Architectural Wonders of Our World: Amazing Structures and How They Were Built

Would the Leaning Tower of Pisa be of any interest if it didn’t lean? According to M.D. Morris, it certainly would be: the bell‐tower of Pisa Cathedral is an “architectural gem”, and “one of the most important monuments of medieval Europe”. It leans 5.5 degrees to the south because it is founded on layers of silt and clay and sand “as soft as foam rubber”. Had the construction process not been interrupted for obscure reasons at various points the tower would almost certainly have fallen over before it was completed. The fragility of the masonry is such that “the stress...