Breathtaking photos of Niagara Falls being frozen over have gone viral ever since the U.S. and Canada was pelted with the polar vortex. But though the frozen-over falls are beautiful to look at, all is not what it seems. Some of the pictures being shared on social media sites were taken well before the polar vortex of 2014.

However, Aaron Harris, a photographer for Reuters, took some stellar icy pictures of the 167-foot frozen falls Wednesday after the famous natural attraction partially froze when temperatures hit record lows on Tuesday, Yahoo reported. The temperature in Ontario, Canada, on Tuesday was reported at minus 2 degrees Fahrenheit. The news site said the ice formed on the horseshoe part of the falls, which is on the Canadian side of the infamous waterfall. 

Though it’s extraordinary for the Falls to freeze, it’s not the first time it has happened. There are supposedly pictures from the early- and mid-1900s that show an iced waterfall in the archives at Niagara Falls Public Library, but experts aren’t confident they’re authentic images. 

As Yahoo pointed out, even though Harris’ photos of a frozen Niagara Falls are authentic, others circulating the Web are phonies. Or, at least, they weren't photographed during the polar vortex of 2014.

Buzzfeed was one of the first sites to point out that a viral image of an icy Niagara Falls was actually uploaded to Flickr in 2007.

The news site then went on to point out that another popular picture posted on Twitter by Google Earth Pics of a partially frozen Niagara Falls was actually taken in 2012.

Niagara Falls, though mostly iced over right now, is expected to thaw out next week when temperatures at the U.S. and Canadian border are expected to hit 46 degrees.

A similar viral picture of the St. Joseph Lighthouse in Michigan has made its way around popular social media sites like Facebook and Twitter, even though it was taken a year earlier by photographer John McCormick, as USA Today noted.

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