Behind the Cathedral and the Tower is the Cathedral Museum, containing may works of art which at one time were in and around the Cathedral and other buildings in the Field of Miracles. Over time these works were moved inside for safety or preservation. There are a wide variety of pieces housed here despite the building’s relatively small size. The accompanying signage is good and everything is arranged logically. Allow an hour or so to really soak in the museum’s collection.
The museum building has a nice inner courtyard. One of my favorite views of our visit to Pisa is taken from the second floor above the museum courtyard, with a unique view of the Leaning Tower and the Cathedral.