Ionia is the largest city in, and the county seat of, Ionia County, Michigan, United States. The population was 11,394 at the 2010 census. Every July it hosts what is said to be the world’s largest free-admission fair. The city is mostly within Ionia Township, with small portion extending into Easton Township and Berlin Township, but is politically autonomous of the townships. Before Euro-American migration, this was the location of an Odawa village. The leader of the Odaw here was Cobmoosa. His people planted crops here in 1833 but when Dexter and his associates arrived, they sold these crops to Dexter and relocated to the Flat River. In the 1850s, they were relocated to Oceana County.
According to the United States Census Bureau, the city has a total area of 5.48 square miles (14.19 km2), of which 5.35 square miles (13.86 km2) is land and 0.13 square miles (0.34 km2) is water. Ionia is between Michigan’s capital, Lansing, and its second largest city, Grand Rapids. This climatic region is typified by large seasonal temperature differences, with warm to hot (and often humid) summers and cold (sometimes severely cold) winters. This region is also prone to dense and heavy fog, along with flooding (sometimes very damaging) due to the Grand River that flows through the city, during the spring. According to the Köppen Climate Classification system, Ionia has a humid continental climate, abbreviated “Dfb” on climate maps.
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