A recent study published in Biology Letters may have solved the mystery of the infamous "Chicago Rat Hole" on the sidewalk.
Scientists believe that the outline is not of a rat, but more likely a squirrel, based on measurements of the imprint.
The impression resembles a squirrel: stocky and semi-aquatic, with webbed feet.
The Chicago Rat Hole was located near Roscoe Street and Damen Avenue before it was removed.
The mystery of that infamous "Chicago Rat Hole" on the sidewalk may be solved!
Author's summary: Researchers solve Chicago Rat Hole mystery.