Bordering Colorado, the majority of this unit is in the Carson National Forest and includes San Antonio Mountain and the Cruces Basin Wilderness. This unit is largely public land and offers hunters a plethora of access options. A large array of terrain types will be found here from open prairies to aspen choked hill sides.

Great public access is found here along with decent game densities.

This unit is east of US Highway between Colorado and Tres Piedras. A free-standing volcanic mountain, 10,908-foot San Antonio Mountain, is just west of the highway. A hunter hiking from the highway to the peak climbs almost 2,500 feet in less than 3 miles. High plains from about 8,100-9,100 feet above sea level surround the mountain. Several small lakes are northwest of the mountain on the east side of the San Antonio River. Farther northwest runs another river, Los Pinos, which enters rains through Toltec Gorge close to the Colorado border and drains many high mountains and ridges from 9,000 to more than 10,000 feet in elevation, including the Cruces Basin Wilderness.

High plains that are mostly between 8,100 and 9,100 feet in elevation are mostly covered by grasses and low brush with several creeks and rivers cutting through them, often lined with trees. Pinyon pines, ponderosa pines and junipers cover many of the low hills. High elevations feature aspen forests as well as conifer forests with spruce, firs and pines. Many parks and meadows are among the trees. In some areas, clearcuts have opened up the terrain, such as on the north side of San Antonio Mountain.

Most of the unit is in the Carson National Forest, which has good road access and a network of maintained and unmaintained roads. Some large pieces of private land are south and southwest of San Antonio Mountain, otherwise private tracts are mostly small and situated along rivers or creeks and mostly along roads that are open to the public. Vehicles may not enter the Cruces Basin Wilderness, which is not as rugged and steep as many other wilderness areas in the West and is a favorite destination of many elk hunters.

Most hunters hiking in the wilderness use backpack tents while horseback hunters sometimes pack wall tents. Hunters outside the wilderness typically camp along dirt roads, often within view of San Antonio Mountain, where elk and deer can be seen every day by hunters who set up high-powered binoculars or spotting scopes on tripods. A campground at Lagunitas, 26 miles north of Tres Piedras, has 12 campsites and is close to the Cruces Basin. Near the Colorado state line are four campgrounds in the Los Pinos area.