This adorable subway dog is going viral — but where are its legs?

A video of a dog riding on the New York City subway is charming — and bewildering — thousands of social media users.

The clip, shared to Reddit’s r/aww forum by user u/unaviable, shows the head of a seemingly large dog sticking out of a suitcase. The post, which shows the animal riding the train next to what appears to be its owner, was upvoted nearly 25,000 times in its first day online.

But there’s one thing question that seemed to be on the mind of several Reddit users: Where is the rest of the dog’s body?

“Why does it look photoshopped? The dog looks huge compared to the size of the bag,” one user commented.

“The dog to bag ratio here is blowing my mind….” another added.

The confusion seemed to stem from the fact that the dog’s head, which appears to be fairly large, doesn’t seem to correspond to a body that could fit inside a relatively small suitcase. However, many users were quick to point out that different breeds of dogs have different head sizes.

“I feel like a lot of young Golden Retrievers have heads that look really big compared to their bodies,” one user wrote.

“Some dogs are weirdly like cat’s with the small spaces they can and enjoy fitting into,” another theorized.

Others offered different theories, such as the idea that the video could be a sort of optical illusion.

“Maybe it’s the angle of the photo, maybe it’s just me … Regardless, that dog looks way larger than the suitcase he’s in,” one user wrote.

Regardless of the mystery, the majority of users just seemed enthralled by the dog’s cuteness.

“Words can not explain how happy this made me,” one user commented.

The dog’s size might remain a mystery, but the reason it was inside a bag is no secret. In 2016, New York’s Metro Transit Authority banned dogs from its subways, unless they were small enough to fit inside a small container, such as a crate.

That law led to a slew of hilarious rule-bending efforts, including this attempt from 2019.

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