The road was designated as a service route for the now defunct Loring Air Force Base.

[citation needed] SR 89 begins at a right-in/right-out intersection with Main Street in downtown Caribou.

SR 89 heads east along the two-lane High Street passing numerous businesses and residences.

Now entering the town center of Limestone, SR 89 passes a mix of houses and businesses before ending at US 1A which carries Main Street (to the south) and Van Buren Road (to the north).

The intersection is located one block north of the western terminus of SR 229 which provides access to New Brunswick, Canada.