Blue Hole (Castalia)
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 southwest of the Cedar Point amusement park in Sandusky, Ohio.
Blue Hole (Red Sea)
The number of diver deaths in the Blue Hole is not known, one source suggests 130 in the last fifteen years. The majority of those killed were experienced, including highly trained technical divers and diving instructors. There have also been snorkelling deaths at the surface unrelated to the depth of the hole.