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