Blue Hole (Castalia)
The Blue Hole captured the public’s interest because of its size, about in diameter, clarity, vibrant blue hue, and enigmatic "bottomless" appearance. Contrary to prevalent belief, the depth of the Blue Hole is not unknown, but has been sounded and found to be about deep. Water temperature is about throughout the year. Floods and droughts have no effect on temperature or water level. The Blue Hole is fed by a passing underground stream which discharges of water daily into Sandusky Bay to the north, feeding into Lake Erie. The water contains lime, soda, magnesia and iron, and because the Blue Hole is anoxic, it cannot naturally sustain fish. The surrounding terrain is developed on limestone bedrock and exhibits karst topography due to dissolution of the limestone by ground water, creating water-filled sinkholes. The Blue Hole was known to American Indians and was first recorded in history in 1761. Several similar blue holes are known to local residents. The Blue Hole that once was a tourist attraction is now off limits to the public. It is located on the grounds of Castalia Trout Club. It is to be distinguished from another hole similar in size and eerie bluish-green color. This latter hole is owned by the Castalia State Fish Hatchery operated by the Ohio Department of Natural Resources, Division of Wildlife and is open for public viewing.
Great Blue Hill
Great Blue Hill (called Massachusett by Native Americans) is a hill of 635 feet (194 m) located within the Blue Hills Reservation in Milton and Canton, Massachusetts 10 miles (15 km) southwest of downtown Boston. It is the highest point in Norfolk County. The modern name for the hill was given by early European explorers who, while sailing along the coastline, noticed the bluish hue of the exposed granite faces when viewed from a distance (due to Riebeckite). The Blue Hills' eastern slopes face the ocean and lie within Quincy. The area attracted quarrying for its "blue granite".
The name of the Massachusett Indian tribe and their language (and thus the name of the Bay, Colony, Commonwealth/State, etc.) derive from the Massachusett name for the hill: "massa-adchu-es-et", where "massa-" is "large", "-adchu-" is "hill", "-es-" is a diminutive suffix meaning "small", and "-et" is a locative suffix, identifying a place.