Md. Code, Transportation § 21–1125

Notwithstanding any other provision of this title, a person may not drive a low speed vehicle:

(1) On a highway for which the posted maximum speed limit exceeds 30 miles per hour;

(2) On an expressway or another controlled access highway that is signed in accordance with § 21-313 of this title;

(3) On a highway on which driving a low speed vehicle is prohibited by a county or municipal ordinance; or

(4) Across a highway for which the posted maximum speed limit exceeds 45 miles per hour, except at an intersection that is controlled by:

(i) A traffic control signal; or

(ii) A stop sign at each approach to the intersection.