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.
Schuylkill Gap
Schuylkill Gap is a water gap through Blue Mountain located about 3 miles north of Hamburg, Pennsylvania. The borough of Port Clinton, Pennsylvania resides within the gap itself.
Formed in much the same way as Pennsylvania's other water gaps, Schuylkill Gap is near Hawk Mountain, Weiser State Forest, and some State Game Lands. PA Route 61 as well as the Schuylkill River pass through the gap.