The Niagara River is a residual effect of the last Ice Age.
About 15,000 years ago the southern aspect of Ontario was completely covered in ice sheets, which were miles thick. As they moved south, they gouged out great caverns which are now the great lackes.
Melting for the last time, they released massive amounts of melted water into these basins they had created, making the water that is in these lakes, fossil water.
Less than one percent of the lakes water comes from rainfall in modern day,. All of the rest of it came from melting sheets of ice many thousand years ago.
Later in time, about 10,000 years ago, the ice began to retreate and advance again, and the land rebounded when released from the pressure of the ice, rerouting the rivers and the meltwaters they contained.
Niagara River was reduced to about 15% of its current water amount and a much smaller Falls were still in another area.
Later.. actually another five thousand years later, the melting waters were once more rerouted through Ontaria and restored the river to its full amazing power near the whirlpool.
This encounter would have been very brief. Possibly the creatioin of the Falls proper would have lasted very little more than a week or so.
The falls which had been created came to intersect with an old riverbed, which had been sealed and long buried since the Ice age, it ripped out this great gorge, and filled it, wiping it completely clean andwhen it was completed left behind a huge bend in the river, a whirlpool that is known today as Whirlpool Rapids.
The Falls then re-established themeselves near the whirlpool and began to carve their way through solid rock to build themselves.
STill later in time, about five hundred years ago, Goat island was formed by the rivers meetup with some type of obstacle in the river that caused the water to split and form two seperate channels.
If the water becomes cold enough in winter, thick sheets of ice will form that may grow to be fifty or sixty feet thick..and will at times form an icy bridge that will run for several miles.
February 24th of 1888 the local newspaperin Niagara reported to its readers that as many as 20,000 toboganed on the ice or walked on it that week.
Until 1912, visitors were allowed to actually walk out on the ice bridge and look at the waterfalls below them, however in February of 1912 when the ice bridge broke and several tourist died as a result.
Find out more about the Niagara Falls over at Wikipedia »