Ohio Rev. Code § 5533.29: General Thaddeus Kosciusko Memorial Highway.

The road known as state route number two hundred fifty-seven running in a north and south direction, commencing at the municipal corporation of Prospect and extending through the counties of Marion, Delaware, and Franklin to its point of junction with United States route number thirty-three shall be known as the "General Thaddeus Kosciusko Memorial Highway."

The director of transportation may erect suitable markers upon said highway indicating its name.