After several miles, the highway shifts slightly more eastward as it approaches the Cortez Mountains and the Pinon Range.

[2][5] A route approximating the alignment of Eureka–Carlin Road appeared on state highway maps as a narrow, unimproved roadway as early as 1927.

[8] Except for the portion between Palisade and US 40, the road was completely paved by 1956—a road connecting just south of Palisade directly to Carlin (approximating today's alignment of the northernmost reaches of SR 278) was also paved by this time.

However, the Nevada Department of Transportation began renumbering its state highways in the mid 1970s.

On July 1, 1976, the road was renumbered again, to State Route 278, the designation it carries today.