Harvard University, which celebrated its 350th anniversary in 1986, is the oldest institution of higher learning in the United States. Founded 16 years after the arrival of the Pilgrims at Plymouth, the University has grown from nine students with a single master to an enrollment of more than 18,000 degree candidates, including undergraduates and students in 10 principal academic units. An additional 13,000 students are enrolled in one or more courses in the Harvard Extension School. Over 14,000 people work at Harvard, including more than 2,000 faculty. There are also 7,000 faculty appointments in affiliated teaching hospitals.