Unit 586

The Rimrock system—including The Rimrock, Rimrock Divide, and Rimrock Reefs—forms a natural navigation anchor running through the unit's heart and provides excellent glassing terrain. Major summits like Virginia Peak, Sunlight Peak, and Comb Butte serve as visual references across the open country. Dead Horse Lakes, Campfire Lake, and the string of reservoirs (Martinsdale, Lucas, Fox, Higgins) mark reliable water and potential staging areas.

Named creeks including Sourdough, Youngs, Billy, and Forest Creek trace natural drainages that channel through the country. Several historical settlements (Twodot, Martinsdale, Higgins, Melville) provide context for understanding the unit's geography and access points.

The unit spans from 4,163 feet in the lower basins to just over 10,000 feet on the highest ridges, with most terrain sitting between 5,000 and 6,500 feet. Lower elevations feature open grasslands and sagebrush parks characteristic of Montana's foothill prairie. As terrain rises, timber becomes scattered rather than continuous—ponderosa and Douglas-fir patches interspersed with open slopes and ridgetops.

The sparse forest coverage means expansive glassing country with good visibility, though scattered timber provides travel corridors and thermal cover. Ridgelines like The Rimrock and Rimrock Divide offer commanding vantage points above the surrounding basins.

Despite vast terrain, the unit has fair road access with 450 miles of roads creating a connected network, though density is spread across the large area. US Highways 191, 89, and 12 frame the unit's boundaries and offer vehicle access, while secondary roads penetrate to various staging areas and ranches. The combination of vast size, sparse timber, and fair but not dense road network means pressure can concentrate at accessible points—creek bottoms, reservoir areas, established parking spots.

Much of the ridge country and upper terrain sees minimal pressure due to remoteness and lack of convenient access. Terrain complexity (9/10) means getting off-road requires navigation skills and time investment.

Unit 586 encompasses portions of four central Montana counties—Wheatland, Sweet Grass, Meagher, and Park—forming a large foothill zone between the Crazy Mountains and the Absaroka Range. The unit is framed by US Highway 191 on the east (connecting Harlowton through Sweet Grass Creek), Highway 89 on the west, and US 12 and Route 294 forming the northern boundary. This creates a distinct geographic pocket where the prairie meets the mountains, roughly 40 miles east-west and 50 miles north-south, capturing the transition zone where open country breaks into broken ridgelines.

Water is limited but present in defined locations. Major streams include Sourdough Creek, Youngs Creek, and Forest Creek, which flow through the lower basins. A network of reservoirs—Martinsdale, Lucas, Fox, Higgins, Voldseth, and others—captures seasonal runoff and provides reliable livestock water that also benefits wildlife.

Several springs including Spruce Springs, Cinnamon Spring, and Bear Spring offer water in higher terrain, though they require local knowledge to locate. Sweet Grass Creek forms the eastern boundary and represents the largest perennial water feature. Understanding water locations is essential for route planning, as much of the open ridge country can be dry.

Unit 586 is pronghorn country, and the sparse timber mixed with extensive grasslands and sagebrush creates ideal antelope habitat. Early season hunting focuses on the open ridges and basins where pronghorn concentrate, using high vantage points to glass wide country. The scattered timber provides thermal cover and reduces visibility, making morning and evening movement predictable through defined drainages and passes.

Terrain complexity means successful hunters need solid navigation and patience—the country is big enough to harbor good animals but requires methodical glassing and stalk planning. Water sources cluster pressure, making areas away from known reservoirs and creeks potential opportunities. Late season animals tend to migrate to lower elevations as snow approaches higher terrain.