Both segments are low-traffic, two-lane, undivided roads winding through the Piney Woods of Southwest Arkansas.

ArDOT estimates the traffic level for a segment of roadway for any average day of the year in these surveys.

The route runs west through sparsely populated pine forest, curving northward after Sycamore and crossing McNeeley Creek twice.

Highway 51 crosses the Union Pacific Railroad tracks and a former alignment near Beirne, a small mill town.

The highway begins paralleling the Caddo Valley Railroad and South Fork Terre Noir Creek, before crossing both shortly after entering the city limits of Okolona.

Highway 51 turns east to Arkadelphia, passing the Terre Noire Natural Area, which contains blackland prairies and woodland complexes.

[5] It passes through Brown Springs before serving as the western terminus of Highway 222 east of Donaldson.

It runs north through the small town of Rockport before turning westward toward Butterfield and Magnet Cove.

[13] Between Curtis and Gum Springs, a four-mile-long (6.4 km) stretch of concrete pavement built in 1931 remains intact.

Part of the original Highway 51 alignment between Little Rock with Texarkana, the pavement was used until the present section of US 67 was built in 1965.