CUSTER, S.D. – Travelers and residents in the Rapid City area will soon have a smoother commute through one of the region’s most iconic landscapes. Beginning Friday, April 3, 2026, a two-mile stretch of U.S. Highway 16A in Custer State Park is scheduled to reopen to traffic, ending the need for a six-mile gravel detour.

The section of highway, located approximately 14 miles east of Custer and nine miles west of the S.D. Highway 79 intersection, was closed to facilitate the replacement of a box culvert and multiple pipe culverts. While the primary structural work is finished, officials noted that a small portion of the road will remain unpaved for a few more weeks.

Within the two-mile segment, approximately one-tenth of a mile will remain gravel until mid-May, when asphalt is scheduled to be placed, according to the South Dakota Department of Transportation.

The reopening marks a significant milestone in a $15.6 million infrastructure project managed by Paul Reed Construction & Supply Inc. of Gering, Nebraska. In addition to the culvert replacements, the project includes the installation of new guardrails and a 600-foot realignment of the Wildlife Loop Road.

Motorists traveling from Rapid City and surrounding communities should still prepare for some minor disruptions as the weather warms. Starting in May, crews will begin an asphalt mill and overlay across a 13-mile span of Highway 16A between the east and west entrances of the park. This phase of the project will utilize pilot cars and flaggers, with expected travel delays of up to 15 minutes.

Despite the ongoing construction, all Custer State Park amenities remain accessible to the public. The entire project is slated for completion by Oct. 30, 2026.