On and after March 30, 1972, no outdoor advertising shall be erected or maintained within six hundred sixty feet of the nearest edge of the right-of-way and visible from the main traveled way of any highway which is part of the federal-aid primary highways as of June 1, 1991, and all highways designated as part of the National Highway System by the National Highway System Designation Act of 1995 and those highways subsequently designated as part of the National Highway System in this state except the following:

(1) Directional and other official signs, including, but not limited to, signs pertaining to natural wonders, scenic, cultural (including agricultural activities or attractions), scientific, educational, religious sites, and historical attractions, which are required or authorized by law, and which comply with regulations which shall be promulgated by the department relative to their lighting, size, number, spacing and such other requirements as may be appropriate to implement sections 226.500 to 226.600, but such regulations shall not be inconsistent with, nor more restrictive than, such national standards as may be promulgated from time to time by the Secretary of the Department of Transportation of the United States, under subsection (c) of Section 131 of Title 23 of the United States Code, and two-year colleges shall qualify for substantially the same signs as traditional four-year colleges, irrespective of differences in student housing or types of degrees offered;

(2) Signs, displays, and devices advertising activities conducted on the property upon which they are located, or services and products therein provided;

(3) Outdoor advertising located in areas which are zoned industrial, commercial or the like as provided in sections 226.500 to 226.600 or under other authority of law;

(4) Outdoor advertising located in unzoned commercial or industrial areas as defined and determined pursuant to sections 226.500 to 226.600;

(5) Outdoor advertising for tourist-oriented businesses, and scoreboards used in sporting events or other electronic signs with changeable messages which are not prohibited by federal regulations or local zoning ordinances. Outdoor advertising which is authorized by this subdivision (5) shall only be allowed to the extent that such outdoor advertising is not prohibited by Title 23, United States Code, Section 131, as now or thereafter amended, and lawful regulations promulgated thereunder. The general assembly finds and declares it to be the policy of the state of Missouri that the tourism industry is of major and critical importance to the economic well-being of the state and that directional signs, displays and devices providing directional information about goods and services in the interest of the traveling public are essential to the economic welfare of the tourism industry. The general assembly further finds and declares that the removal of directional signs advertising tourist-oriented businesses is harmful to the tourism industry in Missouri and that the removal of directional signs within or near areas of the state where there is high concentration of tourist-oriented businesses would have a particularly harmful effect upon the economies within such areas. The state highways and transportation commission is authorized and directed to determine those specific areas of the state of Missouri in which there is high concentration of tourist-oriented businesses, and within such areas, no directional signs, displays and devices which are lawfully erected, which are maintained in good repair, which provide directional information about goods and services in the interest of the traveling public, and which would otherwise be required to be removed because they are not allowed to be maintained under the provisions of sections 226.500 through 226.600 shall be required to be removed until such time as such removal has been finally ordered by the United States Secretary of Transportation;

(6) The provisions of this section shall not be construed to require removal of signs advertising churches or items of religious significance, items of native arts and crafts, woodworking in native products, or native items of artistic, historical, geologic significance, or hospitals or airports.