Ohio University (often referred to as OHIO, OU, or historically, The Ohio University) is a public research university in Athens, Ohio.[7] The first university chartered by an Act of Congress[8] and the first to be chartered in Ohio,[9] it was chartered in 1787 by the Congress of the Confederation and subsequently approved for the territory in 1802 and state in 1804,[10] opening for students in 1809.[11] Ohio University is the oldest university in Ohio, the tenth oldest public university in the United States and the 32nd oldest among public and private universities.[12] As of fall 2020, the university's total enrollment at Athens was slightly more than 20,000, while the all-campus enrollment was just over 33,000.[13]