Pretty Rocks Bridge complete, setting stage for return to Denali Park Road’s west end

Photo: Pretty Rocks Bridge in September, 2025.

By SUZANNE DOWNING

Sept. 3, 2026 – Five years after a massive landslide cut off vehicle access to the western reaches of Denali National Park, the new Pretty Rocks Bridge is complete.

The National Park Service, Federal Highway Administration and project partners marked the milestone Thursday with a ribbon-cutting ceremony near Mile 45 of the Denali Park Road. The roughly 475-foot bridge spans the active Pretty Rocks landslide, reconnecting the eastern and western sections of the road.

Public bus service to Eielson Visitor Center, Wonder Lake and other destinations west of the landslide is expected to resume for the 2027 visitor season.

“This is an exciting milestone for Denali and for everyone who has worked over the past five years to restore access to the west end of the park road,” Denali National Park and Preserve Superintendent Brooke Merrell said in a statement.

“Building a bridge across an active landslide in one of the most remote and challenging environments in the country required extraordinary collaboration, innovation and determination,” she said. “We are grateful to the Federal Highway Administration, our project partners and the many people who made this possible, and we look forward to welcoming visitors back to the west end by bus in 2027.”

The Pretty Rocks landslide forced the National Park Service to close the road in August 2021, interrupting vehicle access to Eielson Visitor Center, Wonder Lake, park residential and maintenance facilities, Kantishna and privately owned properties and tourism businesses beyond the slide.

The closure curtailed how far visitors could travel into the park. In recent years, park buses have stopped at East Fork near Mile 43, rather than continuing through some of Denali’s best-known backcountry landscapes.

The National Park Service and the Federal Highway Administration’s Western Federal Lands Highway Division developed the Polychrome Area Plan as a long-term response to the unstable ground. The approximately $230 million project was financed through a combination of federal transportation, disaster supplemental and infrastructure funding.

Engineers faced steep terrain, complex geology, permafrost, a remote work site and Alaska’s short construction season.

Instead of continuing the losing battle of maintaining a road directly across the moving ground, planners designed the bridge to span the unstable area. The steel truss bridge is about 50 feet tall and 24 feet wide, assembled on the east side of the landslide and then swung into place across the gap in 2025.

The project also employs 23 thermosiphons, which are underground devices designed to help keep the permafrost beneath the eastern end of the bridge frozen and stable.

National Park Service crews are still repairing the road and tackling deferred maintenance at facilities that have been largely inaccessible since 2021.

Hikers and bicyclists have been allowed to travel west of East Fork and cross the bridge since Aug. 27. Park buses, however, will continue to stop at East Fork for the remainder of the 2026 visitor season.