Ithaca is a city in the U.S. state of Michigan. As of the 2000 census, the city had a total population of 3,098. It is the county seat of Gratiot County6.
According to the United States Census Bureau, the city has a total area of 10.6 km2 (4.1 mi2). 10.6 km2 (4.1 mi2) of it is land and none of it is covered by water