I have to disagree, there's plenty to do and see in Pisa. While it can't compete with Florence, right next to the leaning tower the cathedral and the baptistery contain some of the earliest examples of renaissance sculpture, and the sinopia museum gives insight into the technology of fresco painting. There are also several other museums and churches scattered around the city center and the riverbank, worth to pop in even if you're just trying to escape the summer heat.

And as others mentioned, its airport and train station make it a convenient hub to explore the surrounding area, including Calci, Lucca, Cinque Terre, and Livorno.