The University of Michigan (U-M, UM, UMich, or U of M), frequently referred to simply as Michigan, is a public research university in Ann Arbor, Michigan, United States. Founded in 1817 in Detroit as the Catholepistemiad, or University of Michigania, 20 years before the Michigan Territory became a state, the University of Michigan is the state's oldest university. In 1821, the university was officially renamed the University of Michigan. It moved to Ann Arbor in 1837 onto 40 acres (16 ha) of what is now known as Central Campus. Since its establishment in Ann Arbor, the university campus has expanded to include more than 584 major buildings with a combined area of more than 34 million gross square feet (780 acres; 3.2 km2) spread out over a Central Campus and North Campus, two regional campuses in Flint and Dearborn, and a Cente in Detroit. The University was a founding member of the Association of American Universities