After April 4, 1970, no new or additional off-site signs or billboards shall be erected, nor shall any existing off-site sign or billboard be altered or relocated, within six hundred sixty (660) feet of the exterior right-of-way line of any portion of a freeway or of a route for a freeway which has been adopted by the State Highway Commission, if the copy of such off-site sign or billboard is or would be visible by persons traveling on such freeway or proposed freeway. (Ord. 2016-0010 § 38; prior code § 3.12.191)