Ann Arbor Charter Township is a charter township of Washtenaw County in the U.S. state of Michigan. The population was 4,673 at the 2020 census. The township borders the city of Ann Arbor and contains numerous exclaves, but the two are administered autonomously.

The Huron River is a 130-mile-long (210 km) river in southeastern Michigan, rising out of the Huron Swamp in Springfield Township in northern Oakland County and flowing into Lake Erie, as it forms the boundary between present-day Wayne and Monroe counties. Thirteen parks, game areas, and recreation areas are associated with the river, which passes through the cities of Dexter, Ann Arbor, Ypsilanti, Belleville, Flat Rock and Rockwood that were developed along its banks.