From there, it heads east through Osage County for 20 miles (32 km) without crossing any other highway.

Headed north from Salina, the two highways begin to cross some mountainous terrain.

North of Spavinaw, SH-20 splits off to the east, running through unincorporated Chloeta and serving as the eastern terminus of SH-28.

On April 10, 2008, a section of SH-20 in Rogers County near Keetonville, west of Claremore, was closed due to a landside caused by heavy rains.

[2] A 500-foot (150 m) section of roadbed was washed away, forming a large crack in the pavement and damaging the guardrail.