If you are traveling northbound, there is a phone at the south end of the bridge. Instructions for using the phone are posted in the phone box. The phone is located on the shoulder of I-75 just north of the Jamet Street exit to Mackinaw City (near Audies Restaurant). You do not need to exit the freeway. Just past the exit, you can pull over to the right and park on the shoulder. The phone box is located on the right-of-way fencing. The box is green and easily spotted. If this is still unclear, please call us at 906-643-7600.