Ohio Rev. Code § 5511.09
Within a county, any highway or bridge that is part of the state highway system may be officially assigned a distinctive name, commemorative of an historical event or personage or a commonly accepted and appropriate name, by which the highway or bridge is known. Upon agreement of the governing bodies of the county and each township and municipal corporation within the county through which the highway extends or in which the bridge is located, a request for approval of the highway or bridge name may be submitted to the director of transportation. The agreement shall be indicated by a resolution from each governing body in support of the proposed highway or bridge name. The resolution may not be withdrawn, amended, or repealed for thirty days following receipt of the resolution by the requesting authority, or during the time the request is pending before the director.
Within thirty days after receipt of such a request, the director shall inform the requesting authority of the director's decision. If the director approves the request, the requesting authority, at its own expense, may erect markers indicating the name of the highway or bridge within the county, provided that any marker so erected shall conform to the law of this state and to federal law and shall be in accordance with the directives for the signing of named memorial highways included in the manual adopted by the department of transportation under section 4511.09 of the Revised Code.
Only one name per county shall be assigned to a highway or a bridge under this section, and the name shall apply to the entire extension of the highway or the entire portion of the bridge within the county. A name assigned to a state highway or part thereof or a bridge under this section may be altered or abolished, pursuant to approval of the director, in the same manner as provided for assignment of the original name.
This section shall not in any way modify, limit, or restrict the authority of a municipal corporation to designate within the municipal corporation, the name of a highway or a bridge that is part of the state highway system. If a municipal corporation has acted pursuant to its authority and designated the name of a highway or bridge within the municipal corporation, no other name may be assigned to that highway or bridge under this section.
R.C. §5511.09