The Province reports, “The falls have frozen over. As the so-called “polar vortex” has sent temperatures plunging throughout most of North America in the past week, visitors to Niagara Falls in southern Ontario have been treated to a rare sight: chunks of ice clinging to the rocks where water usually rushes freely.

It was clear something was happening as early as Jan. 2, when this woman posed at the falls on a day when temperatures dipped to -14 C:

On the same day, an Instagram user posted this shot of the freezing river.

Things got serious on Tuesday, when the temperature dropped to -19 C and Google Earth sent out this pic:

A couple of photos posted to Twitter earlier today (-13 C) show the extent of the icing near the falls:

As rare as it is to see this degree of freezing at the falls, it’s not the first time. In fact, Niagara Parks dug up this image from the archives, of people posing by the frozen falls in 1890:

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