Wikipedia:WikiProject U.S. Roads/Colorado/1968 renumbering

SH 1: south of Fort Collins removed, as it was redundant with US 287 and US 85
SH 2: west and east of Denver removed; carrier route of US 40 west of Denver and carrier route of US 6 from Denver to Sterling and of US 138 from Sterling to Nebraska; note that it was rerouted over SH 153 from US 40 to SH 30
SH 3: eliminated; carrier route of US 85 from the Wyoming Border to Denver
SH 4: eliminated; carrier route of US 6 from the Utah Border to US 24, and US 24 from there to Kansas
SH 6: eliminated; carrier route of US 50 from Grand Junction to Kansas one section along 4th/5th Street in Grand Junction turned back; duplicated US 6
SH 8: west and east of Denver eliminated; carrier route of US 285 west of Denver and carrier route of US 40 east of Denver; portions renumbered SH 36 and SH 40
SH 10: West of Walsenburg removed, as it was redundant with US 160 (section to the north now US 491)
SH 11: eliminated; carrier route of I-25 from North Neveda Avenue (US 87) to South Nevada Avenue (US 87) in Colorado Springs
SH 12: section east of La Junta eliminated, as it was the carrier route of US 350
SH 14: section east of Sterling eliminated, as it was the carrier route of US 6; a section northwest of Fort Collins was the carrier route of US 287, but this is now a simple concurrency
SH 15: section north of Monte Vista eliminated, as it was the carrier route of US 285
SH 16: eliminated; carrier route of US 34 from Granby to Wiggins
SH 17: section from Pagosa Springs to New Mexico eliminated, as it was the carrier route of US 84; section from Alamosa to Antonito was the carrier route of US 285; but that is now a concurrency
SH 18: eliminated; carrier route of the US 50 freeway from Pueblo to Avondale
SH 19: eliminated; carrier route of US 550 from New Mexico to Montrose
SH 20: eliminated; carrier route of BL I-70 in Grand Junction
SH 24: eliminated and renumbered SH 44 to avoid duplication with US 24
SH 25: eliminated and renumbered SH 55 to avoid duplication with I-25
SH 27: eliminated; carrier route of I-25 from South Nevada Avenue (US 87) in Colorado Springs to Fountain
SH 32: created as a renumbering of SH 72 spur; note that a then recently-decommissioned one went from US 666 (now US 491) at Cortez west via Montezuma County Road G
SH 33: eliminated; carrier route of I-225; reused immediately as a renumbering of SH 36; conflicted with US 36
SH 36: eliminated; renumbered SH 33 to avoid duplication with US 36 and new SH 36; reused immediately on former portion of US 36; conflicted with US 40
SH 40: eliminated; carrier route of US 164 from Four Corners to US 666 near Cortez; reused immediately on former portion of US 40
SH 44: created as a renumbering of SH 24
SH 49: eliminated; carrier route of US 36 from Denver to SH 7 in Boulder
SH 50: became an extension of SH 105 from I-25 to SH 83 in Monument (this section no longer a state highway); conflicted with US 50
SH 51: eliminated; carrier route of US 385 from Granada to Nebraska (note that north of Julesburg was SH 166 before 1953); reused immediately as a renumbering of SH 70 north of US 6
SH 54: eliminated; carrier route of US 34 from Brush to Nebraska
SH 55: created as a renumbering of SH 25
SH 59: section south of Kit Carson eliminated; carrier route of US 287 from Kit Carson to Oklahoma
SH 66: section from US 34 in Estes Park to Lyons eliminated, as it was the carrier route of US 36, took over routing of SH 262
SH 70: eliminated; section south of Business I-70 was carrier route of US 285; north of I-76 renumbered SH 51
SH 72: extended north over SH 160 from SH 119 to SH 7; rerouted on Ward Road instead of Ralston Road/ Wadsworth Road; section along I-70 from Wadsworth Road to Colfax eliminated, as it was a carrier route; SH 72 Spur renumbered SH 32
SH 75: Section from US 85 west and north eliminated, as it became an extension of SH 88; rerouted east along SH 87 from US 85 via Littleton Boulevard and Broadway to US 285 (note that the former SH 87 section and Bowles Avenue sections are now city streets)
SH 76: not renumbered immediately, as there was no I-76; renumbered to SH 78 when I-76 was created
SH 78: eliminated; carrier route of US 6 from US 24 to SH 91; reused on former SH 76 when I-76 was created
SH 80: eliminated; became an extension of SH 141 from Dove Creek to Naturita to avoid duplication with I-80S
SH 84: eliminated; renumbered SH 134 to avoid duplication with US 84
SH 87: eliminated; became an extension of SH 75 (now Littleton Boulevard and Broadway) from US 85 to US 285 to avoid duplication with US 87
SH 88: extended west and north from US 85 and north to BU 1-70
SH 91: section from Copper Mountain to US 40 in empire eliminated, as it was the carrier route for US 6
SH 100: main route eliminated, as it was the carrier route of US 160 from US 350 to Kansas. Only the spur (which was SH 197 before the cutback in 1952) remained, and it became the main route.
SH 102: eliminated; carrier route of US 36 from US 40 (Now SH 40) to Kansas
SH 105: extended from I-25 to SH 83 over SH 50
SH 106: eliminated; carrier route of US 666 (now US 491) from Cortez to New Mexico
SH 123: eliminated; carrier route of US 287 from SH 14 to Wyoming
SH 134: created as a renumbering of SH 84
SH 141: extended over SH 80 from Naturita to Dove Creek.
SH 153: eliminated; replaced by SH 2 from US 285 to US 40
SH 160: eliminated; replaced by SH 72 from SH 119 to SH 7 to avoid conflict with US 160
SH 163: eliminated; carrier route of US 285 from SH 17 to New Mexico
SH 182: eliminated; carrier route of US 6 from US 40 in Idaho Springs to I-25 in Denver
SH 185: eliminated; carrier route of I-25 from Castle Rock north via Denver to Wyoming
SH 192: eliminated; route turned back
SH 200: eliminated; route turned back
SH 262: eliminated; Renumbered as part of SH 66