49 U.S.C. § 31114: Access to the Interstate System

(a) Prohibition on Denying Access.—A State may not enact or enforce a law denying to a commercial motor vehicle subject to this subchapter or subchapter I of this chapter reasonable access between—(1) the Dwight D. Eisenhower System of Interstate and Defense Highways (except a segment exempted under section 31111(f) or 31113(e) of this title) and other qualifying Federal-aid Primary System highways designated by the Secretary of Transportation; and (2) terminals, facilities for food, fuel, repairs, and rest, and points of loading and unloading for household goods carriers, motor carriers of passengers, any towaway trailer transporter combination (as defined in section 31111(a)), or any truck tractor-semitrailer combination in which the semitrailer has a length of not more than 28.5 feet and that generally operates as part of a vehicle combination described in section 31111(c) of this title. (b) Exception.—This section does not prevent a State or local government from imposing reasonable restrictions, based on safety considerations, on a truck tractor-semitrailer combination in which the semitrailer has a length of not more than 28.5 feet and that generally operates as part of a vehicle combination described in section 31111(c) of this title.