Harvard University is a private Ivy League research university in Cambridge, Massachusetts, with about 6,800 undergraduate students and about 14,000 postgraduate students. Established in 1636 and named for its first benefactor, clergyman John Harvard, Harvard is the United States' oldest institution of higher learning. Its history, influence, wealth, and academic reputation have made it one of the most prestigious universities in the world. The Harvard Corporation, chartered in 1650, is the governing body of Harvard. In its early years, Harvard College primarily trained Congregational and Unitarian clergy, although it has never been formally affiliated with any denomination. Its curriculum and student body were gradually secularized during the 18th century, and by the 19th century, Harvard had emerged as the central cultural establishment among Boston elites. Following the American Civil War, President Charles W. Eliot's long tenure (1869-1909) transformed the college and affiliated professional schools into a modern research university; Harvard was a founding member of the Association of American Universities in 1900.A. Lawrence Lowell, who succeeded Eliot, further reformed the undergraduate curriculum and undertook aggressive expansion of Harvard's land holdings and physical campus. James Bryant Conant led the university through the Great Depression and World War II; he began to liberalize admissions after the war. The university is organized into eleven principal academic units—ten faculties and the Radcliffe Institute for Advanced Study—with campuses throughout Greater Boston: its 209-acre (85 ha) original undergraduate campus is centered on Harvard Yard in Cambridge, approximately 3 miles (5 km) northwest of Boston; the business school and many athletics facilities, including Harvard Stadium, are across the Charles River in the Allston neighborhood of Boston; and the medical, dental, and public health schools are in the Longwood Medical Area. Harvard's endowment is worth $40.9 billion, making it the largest of any academic institution. Harvard is a large, highly residential research university. While the nominal cost of attendance is high, the university's sizeable endowment allows it to offer generous, no-loan financial aid packages and use need-blind admission. The Harvard Library is the world's largest academic library system, comprising 79 individual libraries holding about 20.4 million items. Harvard's alumni include eight U.S. presidents, more than thirty foreign heads of state, 188 living billionaires, 369 Rhodes Scholars, and 252 Marshall Scholars. As of October 2019[update], 160 Nobel laureates, 18 Fields Medalists, and 14 Turing Award winners have been affiliated as students, faculty, or researchers. In addition, Harvard students and alumni have won 10 Academy Awards, 48 Pulitzer Prizes, and 108 Olympic medals (46 gold, 41 silver, and 21 bronze), as well as founded many notable companies worldwide.