HD 640 covers the far southeast corner of Montana along the Wyoming and South Dakota border country—the Little Missouri River drainage near Alzada, scattered ponderosa-pine breaks, and the rolling sage-and-grass prairie running into Crook County WY and Harding County SD. Elevations run from about 3,000 feet on the Little Missouri bottom to 4,500 feet on the higher pine-covered buttes. The country is closer in feel to the western Black Hills than to most of Montana—isolated ponderosa pine ridges and buttes rising out of sage prairie, with sandstone outcrops, juniper-and-mountain mahogany draws, and cottonwood-and-willow corridors along the Little Missouri and the seasonal creek drainages. Mule deer use the timbered breaks and rocky benches; whitetail concentrate in the river bottoms; pronghorn work the open prairie in good numbers; some elk move through the breaks; turkeys (Merriam's) in the pines. Custer Gallatin NF (Sioux Ranger District) holds limited timber tracts, BLM scatters through, and the bulk of the country is private ranchland. Block Management is essential. US-212 east-west is the only paved access; county and BLM dirt roads handle the rest, all gumbo when wet. Alzada is barely a place—the Stoneville Saloon, a gas pump, a few houses; Belle Fourche SD is just over the border to the southeast and a more practical supply stop; Broadus is northwest. Cell service is essentially gone. Most successful hunts here are landowner-permission hunts from hunters who built relationships over multiple seasons. The country is quiet and the animals are real for those willing to put in the work.