Overview
The Centennial Trail is the spine of the Black Hills trail network: 111 miles from Bear Butte State Park near Sturgis in the north to Wind Cave National Park in the south, traversing the full length of Black Hills National Forest through ponderosa pine, granite ridges, meadows, and creek drainages. The Iron Creek to Alkali Creek section near Pactola Reservoir is one of the most accessible and scenic middle portions of the trail, offering 8 miles of varied terrain with reservoir views and genuine forest character, away from the tourist corridor that concentrates around Sylvan Lake and the Custer State Park trails.
This section of the Centennial Trail runs north to south through the central Black Hills, crossing the rolling terrain that characterizes the forest at mid-elevation (roughly 4,500 to 5,200 feet). Pactola Reservoir, the largest lake in the Black Hills, is visible from ridgeline sections of the trail, giving the route a visual anchor that the denser forest sections lack.
The Route
Miles 0 to 2: Iron Creek Trailhead to Ridge. Starting from the Iron Creek Trailhead on Highway 44, the trail climbs through ponderosa pine forest in the first 2 miles, gaining the primary ridge that the route follows south. The tree cover is dense in this section, with the forest floor carpeted in needles and the occasional granite outcrop breaking through.
Miles 2 to 4.5: Ridge Traverse with Pactola Views. The trail stays on or near the ridge for the middle section, and Pactola Reservoir appears to the east in clearings and from the highest points. The reservoir is visible as a blue expanse below the ridge, with the dam visible at the south end. This is the most photographed section of the route, and the best place to take a break.
Miles 4.5 to 8: Descent to Alkali Creek. The trail descends from the ridge toward the Alkali Creek drainage in the final section, passing through a transition zone where the forest opens into meadow patches before entering the creek corridor. The Alkali Creek Trailhead is the terminus for the point-to-point route.
Multi-Day Context
This section is a good way to experience the character of the full Centennial Trail before committing to a multi-day end-to-end trip. The full 111-mile trail is one of the underrated long-distance hikes in the Great Plains region: it's not the Sierra Nevada or the Colorado Rockies in terms of elevation and terrain, but it's a genuine wilderness experience through a distinctive landscape that most long-distance hikers haven't done. Most parties complete the full trail over 6-9 days, depending on pace and the amount of side exploration.
For an overview of dispersed camping on national forest land, including what's permitted and how to choose a campsite, see the guide on how to get a national forest camping permit.
Wildlife
White-tailed deer, pronghorn (in meadow sections), wild turkey, and mule deer are all likely to be seen on this route. The forest here is less trafficked than the southern Black Hills trails, which means wildlife is generally less habituated to human presence. Mountain lions inhabit the Black Hills, and while encounters are rare, the SDGFP publishes guidance on mountain lion safety worth reviewing before backcountry travel.
Review Leave No Trace principles before any multi-day trip on the Centennial Trail. Food storage is important: black bears have been documented in the southern Black Hills, and proper camp hygiene applies throughout. See bear canister requirements for food storage guidance.
Getting There
Iron Creek Trailhead: From Rapid City, take SD-44 west approximately 20 miles to the Iron Creek Trailhead sign on the south side of the highway. Free parking is available at the pullout. Drive time from Rapid City is roughly 30 minutes.
Alkali Creek Trailhead (for car shuttle): From the Iron Creek Trailhead, continue west on SD-44 and then south on forest roads to the Alkali Creek access point. Consult the Black Hills National Forest map for the exact approach, as the forest road system in this area requires advance navigation planning.
The Centennial Trail map is available as a free download from the Black Hills National Forest website. The map includes all trailhead locations, water sources, and camping areas along the full 111-mile route.
Before You Go
This section of the Centennial Trail is in the northern part of the Black Hills, away from the Custer State Park fee boundary. No day-use fee is required at the Iron Creek Trailhead. For any overnight trip, standard national forest camping regulations apply (no campfire permits required in South Dakota for backcountry camping outside of fire restrictions, but check current conditions). See checking conditions before you go for USFS alerts and current conditions resources for the Black Hills.