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The American Falls look spectacular at night, when it is lit with various combinations of coloured lights.
Over the last century the American Falls has undergone a dramatic face lift due to natural forces of erosion.
The natural bedrock is composed of soft shale and limestone. Over the years the continual flow of water causes large sections of bedrock to fall and remain at the base of the cataracts.
Geologists predict that eventually the American Falls will transform into a succession of descending rapids.
The diversion of water above the falls has slowed the forces of erosion. It is estimated that 75,000 gallons of water flow over the American Falls each second, amounting to only 10% of Niagara's total waterflow.
No one has ever dared to conquer the American Falls in a barrel. All daredevil activities have always concentrated on the Canadian Horseshoe Falls because it has a larger waterflow and fewer rocks at its basin.