605 ILCS 5/10-503

Every bridge so owned, acquired or controlled by such municipality and the approaches thereto when in whole or in part outside the corporate limits thereof shall be subject to the municipal control and ordinances of such municipality, the same to all intents and purposes and in effect, as though such bridge and approaches thereto were entirely situated within the corporate limits of such municipality, and in such case the county may assist in the construction of such bridge as is provided by law.