A spur route extending west to Mora was originally added with SSH 9B and re-added with SR 110 in 1991.

SR 110 begins as La Push Road at an intersection with US 101 in Forks, located between the Sol Duc and Calawah rivers.

The highway travels southwest towards the Pacific Ocean, intersecting its spur route to Mora before crossing the Bogachiel River and ending at the entrance to Olympic National Park.

[4] SR 110 was established in 1991 on the existing La Push Road from US 101 in Forks to Olympic National Park,[2] previously part of SSH 9B.

SSH 9B and a spur route to Mora was designated in 1937 as part of the newly created Primary and secondary state highways,[5] but was removed in 1955.