There is a great deal of variation among academic libraries based on their size, resources, collections, and services. The Harvard University Library is considered to be the largest strict academic library in the world, although the Danish Royal Library—a combined national and academic library—has a larger collection. Another notable example is the University of the South Pacific which has academic libraries distributed throughout its twelve member countries. The University of California operates the largest academic library system in the world, it manages more than 34 million items in 100 libraries on ten campuses.