(a) The following highways in Hunt County are designated as the John L. Horn Memorial Parkway:
(1) the portion of Farm-to-Market Road 1570 between its intersection with State Highway 34 and State Highway 66; and
(2) Spur 1570 between its intersection with State Highway 66 and U.S. Highway 380.
(b) Subject to Section 225.021(c), the department shall:
(1) design and construct markers indicating the designation as the John L. Horn Memorial Parkway and any other appropriate information; and
(2) erect a marker at each end of the parkway and at appropriate intermediate sites along the parkway.