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Blue Hole

BLUE HOLE   This "blue hole" and three others exposed in the valley are the only ground water windows in the 85 square mile Lost River Karst Drainage Basin.  For over a century this "blue hole"...

BLUE HOLE
 
This "blue hole" and three others exposed in the valley are the only ground water windows in the 85 square mile Lost River Karst Drainage Basin.  For over a century this "blue hole" has been thought to be "bottomless."  This assertion, said to be based on railroad engineer's sounding setting the depth at 437 feet gave [...]
 
Submitted by Bryan Arnold 
@nanowhiskers

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