The Colorado Joint Line is a pair of mainlines that run from Denver to Pueblo, owned by BNSF and Union Pacific. BNSF's line is the Pikes Peak Subdivision. UP's is the Colorado Springs Subdivision.
The Joint line started in 1871 by the Denver & Rio Grande to be a railroad that went from Denver to El Paso Texas to connect to Mexico's lines. The line never went that far down south, so the D&RG just ended it at Pueblo and went west through the Tennessee Pass. ATSF would then build their part of the line in 1888, directly paralleling D&RG's line. Colorado & Southern also built a line down south, next to ATSF and D&RG's lines, but was torn up in 1919, after the lack of rail traffic. Up until WW1, the two lines were competing until the United States Railroad Administration mandated that all traffic would be a joint operation. Currently, the lines are mostly still two separate tracks, with BNSF's track being for southbounds, UP's for northbounds. The lines used to be separate south of Palmer Lake, but ATSF's track was ripped up and DRGW's track is the remaining track for all movements between Palmer Lake and Fountain.
