In the 1st millennium (or the 1000’s or the 11th century) the city of Pisa was becoming an important Italian seaport. Its fame and power grew gradually as the people of Pisa were involved in various military conflicts and trade agreements. In 1063 the Christian city of Pisa attacked the Muslim-ruled city of Palermo (Pal-air-mo). The attack was successful and the conquerors returned to Pisa with a great deal of treasure. To show the world just how important the city was, the people of Pisa decided to build a great cathedral complex called “the Field of Miracles”. Part of that plan was an 8 story bell tower.

On August 9th, 1173 construction began on the bell tower. A foundation for the tower was built of a 3 foot deep mixture of clay. After 5 years of construction they had completed three out of eight floors of the structure, but quickly noticed a problem. It turned out the clay that they used for the foundation wasn’t nearly as strong as they thought and wasn’t able to keep the tower upright. Even everyday citizens could see that the tower had already began to lean. This wasn’t new in Pisa as the river city has soft grounds and a number of other structures have exhibited this same behavior. (More on the podcast)