The Blue Hole is a fresh water pond located in Castalia, Erie County, Ohio, in the United States. From the 1920s to 1990 the Blue Hole was a tourist site, attracting 165,000 visitors annually at the height of its popularity, partly because of its location on State Route 269, about 7 miles (11 km) southwest of the Cedar Point amusement park in Sandusky, Ohio. The Blue Hole was known to American Indians and was first recorded in history in 1761.