Scientists Debunk the "Chicago Rat Hole" Mystery
A recent scientific study has revealed that the infamous "Chicago Rat Hole" was not made by a rat, but rather a squirrel.
The imprint, located in a Roscoe Village sidewalk, had been a source of fascination for Chicagoans and tourists for nearly two years, inspiring numerous TikToks, fan art, and selfies.
The internet’s favorite rat is a rat no more.
Researchers announced in October 2025 that the imprint was likely made by a squirrel that slipped from a nearby tree and landed on wet concrete in the early 2000s.
- The study, published by the Royal Society, compared the imprint's measurements to preserved specimens of eight rodent species.
Author's summary: Scientists confirm squirrel made Chicago hole.