According to the United States Census Bureau, the city has a total area of 20.9 square miles (54km2), of which, 20.9 square miles (54km2) of it is land and 0.04 square miles (0.10km2) of it (0.10%) is water, a little smaller than the fellow city of Westlake, Ohio. Township Number 7 in Range 16 of the Western Reserve received its first permanent American settlers during 1814 from Montgomery County, New York, led by Wilbur Cahoon. The township was administered by Dover township and was part of Cuyahoga County. In 1818, Township Number 7 was organized and first named Xeuma, then later, Troy Township. In 1824, Lorain County was created, and the name of Troy Township was changed to Avon Township. An Avon post office was established in 1825. Eventually, the entire township was incorporated as the city of Avon, because the name of Westlake had already been taken (their number one choice).