Marblehead is also home to a United States Coast Guard station, and to the Marblehead Lighthouse, the oldest continuously operating lighthouse on the Great Lakes. Nearby, in Sandusky Bay, is Johnson's Island, a former Confederate officer POW camp during the Civil War. Marblehead is a village in Ottawa County, Ohio, United States. The population was 762 at the 2000 census. It sits at the tip of the Marblehead Peninsula, which divides Lake Erie proper from Sandusky Bay. In the summer, it is a popular vacation area because of its lake frontage, ferry service to the Lake Erie Islands, quality sport fishery, the nearby Chautauqua at Lakeside, and the Cedar Point amusement park.