Sandusky is a city in and the county seat of Erie County, Ohio, United States. Situated on the southern shore of Lake Erie, Sandusky is loc…Sandusky is a city in and the county seat of Erie County, Ohio, United States. Situated on the southern shore of Lake Erie, Sandusky is located roughly midway between Toledo and Cleveland. According to 2020 census, the city had a population of 25,095, and the Sandusky metropolitan area had 115,986 residents.