Wyoming Highway 258 begins its western end at
US 20 Business/
US 26 Business (Yellowstone Highway) in
Mills and from there travels counter-clockwise around Casper. WYO 258 heads south and crosses the
North Platte River before intersecting W. 13th Street, which also provides access to
Fort Caspar. Continuing south, WYO 258 passes along the western side of the
Central Wyoming Fair Grounds and briefly parallels the North Platte River a short distance before intersecting
Wyoming Highway 220 (CY Avenue), the main artery for traffic coming into Casper from the west. Highway 258 continues east for a small distance and then begins to turn northeast as it travels around the southeastern outskirts of Casper and passes west of the Casper County Club. Now mainly directed north, WYO 258 travels through the eastern neighborhoods of Casper and intersects busy east-west 2nd Street. Casper's
Eastridge Mall lies on the southeastern side of this intersection. A third of mile north of that intersection,
Interstate 25 is intersected at exit 185 as WYO 258 enters the Town of
Evansville. Just past the interstate, WYO 258 reaches its eastern end at
US 20/
US 26/
US 87 (Yellowstone Highway) after . The roadway itself continues north as Curtis Avenue north through Evansville. Wyoming Highway 258 is maintained by the
City of Casper, however when Highway 258 momentarily travels out of the city, state maintenance will begin and end as it does southeast of the city. Casper has taken over maintenance of the portions of the route within its city limits, but for signage purposes the route is still Highway 258. ==Major intersections==