is a city in Sheboygan County, Wisconsin, along the Mullet River. The population was 7,781 at the 2000 census. It is included in the Sheboygan, Wisconsin Metropolitan Statistical Area. The city is located within the Town of Plymouth, but is politically independent. Plymouth is known as "Hub City" because of its location between Milwaukee, Sheboygan, Fond du Lac, and Green Bay.
Plymouth is located at (43.749277, -87.976799).
According to the United States Census Bureau, the city has a total area of 4.2 square miles (10.8 km²), of which, 4.1 square miles (10.6 km²) of it is land and 0.1 square miles (0.2 km²) of it (1.44%) is water.