There are 14 US Post Offices in Gratiot County serving a total of 43,488 residents equating to 3,106 residents per post office. It's estimated that approximately 69,412 packages are handled across the 14 county post offices annually. Gratiot County (/\u02c8\u0261r\u00e6\u0283\u026at/) is a county located in the U.S. state of Michigan. As of the 2010 census, the population was 42,476. The county seat is Ithaca, although its most populous city is Alma. Gratiot County comprises the Alma, MI Micropolitan Statistical Area, which is also included in the Mount Pleasant-Alma, MI Combined Statistical Area. The Gratiot County Courthouse was built in the classical revival style by Claire Allen, a prominent southern Michigan architect. It is one of seven sites in the county listed on the National Register of Historic Places (No. 76002291 added 1976). In June 2012, the 212.8 MW Gratiot County Wind Project opened, the largest wind power installation in the state."