Maryland Transportation Section 21-104

      (a)      Every person riding an animal or driving an animal-drawn vehicle on a roadway has all the rights granted to and is subject to all the duties required of the driver of a vehicle by this title, except for those provisions of this title that by their very nature cannot apply.

      (b)      (1)      Except in Charles, Worcester, and St. Mary's Counties, or as provided in paragraph (2) of this subsection, a person may not ride an animal or drive an animal-drawn vehicle on:

                  (i)      Any divided highway where the posted maximum speed limit is more than 35 miles an hour; or

                  (ii)      Any controlled access highway.

            (2)      In Anne Arundel County, a person may ride an animal on any part of a highway described in paragraph (1) of this subsection, other than on its roadway or shoulder.