Russian troops are entering Ukraine – this much is known – but whether they are mounting a “full-scale invasion,” as one Ukrainian official told CNN, or are mistakenly crossing over, as Moscow itself claims, is uncertain.

Enter Canada.

Our northern neighbor’s delegation to NATO had this useful tweet to remind everyone how, in its words, “Geography can be tough.”

The message has been retweeted more than 17,000 times since it was posted Wednesday morning. No word yet of a Russian response.

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