Blue hole

This is the ocean's black hole which is called blue hole.
A blue hole is a submarine cave or sinkhole. They are also called vertical caves.

Blue holes are roughly circular, steep-walled depressions, and so named for the dramatic contrast between the dark blue, deep waters of their depths and the lighter blue of the shallows around them



The depth limited
because
If who go to there more deeply,
something drag person suddenly.
1000 divers dead because of this.




under the blue hole
there have a beutiful nature
This place is danger but, a lot of divers visited this place.




Blue hole located in Belize which is in Caribbean sea.

blue hole is also, located in the

Dahab in Egypt and Guam's blue hole.