Bridger Junction to Donkey Creek Junction/Gillette

From Bridger Junction (MP 127.3), south apex of the wye with the former Colorado & Southern Denver-Billings line, the line curves east-northeast, single track, CTC, speed limit 50 mph (and 35 mph on all spurs), to Orin Junction (MP 126.2), where the rump of the former Chicago & Northwestern line west to Lander, WY, trails in from the west (i.e., the north leg of the wye), and the line continues east-northeast on the alignment of the former C&NW to Fisher Junction (MP 123.6), where the former C&NW continues east-northeast, and the Powder River Basin line turns just east of due north, past East Fisher (MP 123.1), where Two Main Tracks, CTC, start, and West Fisher (MP 120.3) to Shawnee Junction (MP 117.7), where the UP connection, third leg of a very large wye with the former C&NW line from Fisher Junction, with the east apex at Shawnee, trails in on the east side, there are crossovers and Three Main Tracks, CTC, start.

The line heads curvily north-northwest, past detectors at MP 117.4, detectors at MP 113.5, crossovers at Crossover 110.6 (MP 110.6), detectors at MP 108.3, East Walker, Walker (MP 105.9), where it turns north, West Walker, crossovers at Crossover 103.6 (MP 103.6), detectors at MP 102.8, detectors at MP 98.0, crossovers at Crossover 95.7 (MP 95.7), detectors at MP 93.0, crossovers at Crossover 90.5 (MP 90.5), detectors at MP 88.0, Trinity Rail Services Bill Shop (MP 86.5) on the west side, crossovers at East Bill (MP 85.5), north end of the Bill Shops and south end of the Bill Yard on the west side, detectors at MP 83.3, the yard on the west side at Bill (MP 82.5), and the north end of the yard and crossovers at West Bill (MP 80.8), where it turns north-northwest, and then north again past detectors at MP 75.3, north-northwest past crossovers at Crossover 72.5/Logan (MP 72.5), north past detectors at MP 67.7, northeast and north again.

The spurs to the actual coal mine loading points start at the crossovers at Converse Junction (MP 65.4), where the 1.2 mile spur to the loading loop at Kennecott's Antelope Mine (MP 66.6) heads northwest and the line turns northeast past West Logan (MP 63.0) and crossovers at East Nacco (MP 62.5) to the wye on the east side at Nacco Wye Junction (MP 62.2), where the 6.1 mile spur to the loading loop at Peabody Coal's North Antelope Mine (MP 66.9) and Rochelle Mine (MP 68.3) turns away east, and the line turns north to West Nacco (MP 61.9), just north of due west to detectors at MP 59.4, north to crossovers at Crossover 58.1 (MP 58.1), where the 3MT reduce to 2MT, CTC, northwest, north, north-northeast past crossovers and detectors at Crossover 52.5 (MP 52.5), and north past the junction with the 3.0 mile spur east to Triton Coal's North Rochelle Mine (MP 52.5) at MP 49.5 (MP 49.5).

There are crossovers at Crossover 47.3 (MP 47.3), detectors at MP 45.2, crossovers at Crossover 43.6 (MP 43.6), the south end of the wye junction with the 2.5 mile Reno sub., heading east-southeast to the loading loops at ARCO's Black Thunder Mine and Kerr-McGee's Jacobs Ranch Mine,   at MP 43.0 (MP 43.0), the 8,000 ft. siding at Reno (MP 42.2), the north apex of the wye and crossovers at Crossover 42.1 (MP 42.1), MP 41.4 (MP 41.4), West Reno (MP 40.6), detectors at MP 40.0, detectors at MP 35.9, additional track at Western Gas Processors (MP 34.4), crossovers at Crossover 34.1 (MP 34.1), and Antelope (MP 31.4), a turn just east of due north past detectors at MP 30.1, and north again past crossovers at East Coal Creek (MP 26.5), the wye junction on the east side with the 5.8 mile spur east-northeast to the loading loop at the ARCO Coal Creek Mine at Coal Creek Junction (MP 26.2), and the junction (north apex of the wye), detectors and crossovers at West Coal Creek (MP 25.9).

Sunedco Junction (MP 24.5) is the south junction with the 3.6 mile spur and elongated wye on the west side, past the crossovers and junction at East Cordero Junction (MP 23.8), to the loading loop at Kenecott's Cordero Mine (MP 23.7) and West Cordero Junction, and the line turns just east of due north, past detectors at MP 21.9, the north end of the elongated wye and crossovers at West Cordero Junction (MP 21.1), and Haire (MP 19.3), north-northwest past crossovers at East Rojo Junction (MP 17.8), where the 5.5 mile spur to the loading loop at the Kennecott Caballo Rojo Mine (MP 18.2) heads west-northwest at a wye on the west side extending to a north connection at Rojo Junction (MP 17.4), additional track at Nelson Brothers (MP 17.4), and crossovers at West Rojo Junction (MP 17.3), where the 5.2 mile spur to the loading loop at the Cyprus/Amax Belle Ayr Mine (MP 16.6) heads away on the west side as the line turns north-northeast, past  another connection to that same spur at East Belle Ayr Junction (MP 16.4), start of another elongated wye on the west side reaching on the north end to Caballo Junction (MP 15.0), where there is a wye on the west side with  the 6.2 mile spur to the loading loop at the Peabody Coal Caballo Mine (MP 17.6), the speed limit drops to 35 mph, and UP joint ownership ends.

There are detectors, the north end of that wye, and crossovers at Crossover 14.7 (MP 14.7), and the line turns east, curvily north past detectors at MP 10.3 and crossovers at Crossover 8.2 (MP 8.2), curvily north-northwest past detectors at MP 5.6, north, north-northeast, and north again to crossovers at Donkey Creek Junction (MP 0.4), south apex of the wye on the south side of the former CB&Q Billings/Lincoln line, with east apex at East Donkey Creek Junction and west apex at West Donkey Creek Junction (both at MP 0.0).