The University of Denver is a private research university in Denver, Colorado. Founded in 1864, it is the oldest independent private university in the Rocky Mountain Region of the United States. It is classified among "R2: Doctoral Universities – High research activity". DU enrolls approximately 5,700 undergraduate students and 7,200 graduate students. The 125-acre main campus is a designated arboretum and is located primarily in the University Neighborhood, about five miles south of downtown Denver.