begun in 1773 on sandy silt subsoil, the leaning tower (torre pendente9 started to tilt even before the third storey was finished in 1274.
despite the shallow foundations, costruction continued and the structure was completed in 1530.
the tower's apparent flouting of the laws of gravity has attracted many visitors over the centuries, including the pisan scientist galileo, who climbed to the top to conduct his famous experiments on the velocity of falling objects.
recently its tilt has increased alarmingly: the tower now leans in excess of 5 mt. (16.5 ft.) and remains closed for restoration and underpinning.