Niagara Falls Facts: Do the Falls Freeze Over in Winter?

From the website:

The tremendous volume of water never stops flowing, However, the falling water and mist create ice formations along the banks of the falls and river. This can result in mounds of ice as thick as fifty feet. If the Winter is cold for long enough, the ice will completely stretch across the river and form what is known as the "ice bridge". This ice bridge can extend for several miles down river until it reaches the area known as the lower rapids. Until 1912,visitors were allowed to actually walk out on the ice bridge and view the Falls from below. February 24th of 1888 the local newspaper reported that at least 20,000 people watched or tobogganed on the ice. Shanties selling liquor, photographs and curiosities abounded. On February 4th 1912 the ice bridge broke up and three tourists lives were lost. …

HOWEVER…. The flow of water was stopped completely over both falls
on March 29th 1848 due to an ice jam in the upper river for several hours. This is the only known time to have occurred. The Falls did not actually freeze over, but the flow was stopped to the point where people actually walked out and recovered artifacts from the riverbed!

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