Oso Tunnel Oso Tunnel Archuleta 8268 Chromo
Twin Lakes Reservoir Tunnel Number 2 Twin Lakes Reservoir Tunnel Number 2 Pitkin 12168 New York Peak
Aurora Rampart Tunnel Number 1 Aurora Rampart Tunnel Number 1 Douglas 6079 Platte Canyon
Duffy Tunnel Duffy Tunnel Moffat 6256 Horse Gulch
Beavertail Mountain Tunnel Beavertail Mountain Tunnel Mesa 5075 Cameo
Leon Tunnel Leon Tunnel Mesa 10502 Leon Peak
Harold D Roberts Tunnel Harold D Roberts Tunnel Summit 12346 Montezuma
Laramie Poudre Tunnel Laramie Poudre Tunnel Larimer 9449 Boston Peak
Dille Tunnel Dille Tunnel Larimer 6066 Masonville
Rams Horn Tunnel Rams Horn Tunnel Larimer 9157 Longs Peak
Prospect Mountain Tunnel Prospect Mountain Tunnel Larimer 8842 Longs Peak
Bald Mountain Tunnel Bald Mountain Tunnel Larimer 6726 Pinewood Lake
Rattlesnake Tunnel Rattlesnake Tunnel Larimer 6952 Pinewood Lake
McCullough Tunnel McCullough Tunnel Summit 11922 Breckenridge
Quandary Tunnel Quandary Tunnel Summit 11726 Breckenridge
Hunter Tunnel Hunter Tunnel Pitkin 11096 Meredith
Nast Tunnel Nast Tunnel Pitkin 10407 Nast
Granite Adit Granite Adit Pitkin 10154 Nast
Hagerman Tunnel Hagerman Tunnel Pitkin 11932 Homestake Reservoir
Homestake Tunnel Homestake Tunnel Pitkin 11591 Homestake Reservoir
Phillipson Portal Phillipson Portal Lake 11460 Climax
Ceresco Ridge Portal Ceresco Ridge Portal Lake 11519 Climax
Storke Portal Storke Portal Lake 11197 Climax
Twin Lakes Reservoir and Canal Company Tunnel Number 1 Twin Lakes Reservoir and Canal Company Tunnel Number 1 Lake 13133 Independence Pass
Arrow Tunnel Arrow Tunnel Grand 9728 Fraser
Needle Eye Tunnel Needle Eye Tunnel Boulder 11371 East Portal
Vasquez Tunnel Vasquez Tunnel Clear Creek 11985 Berthoud Pass
Eisenhower Memorial Tunnel Eisenhower Memorial Tunnel Summit 12231 Loveland Pass
Golden Belt Tunnel Golden Belt Tunnel Clear Creek 9724 Grays Peak
Aurora Rampart Tunnel Number 2 Aurora Rampart Tunnel Number 2 Douglas 6585 Kassler
Denver Tunnel Denver Tunnel Mineral 10623 Spar City
Saint John Tunnel Saint John Tunnel Teller 11355 Pikes Peak
Strickler Tunnel Strickler Tunnel El Paso 11837 Pikes Peak
Carlton Tunnel Carlton Tunnel Teller 9157 Cripple Creek South
Roosevelt Tunnel Roosevelt Tunnel Teller 9367 Cripple Creek South
Apishapa Arch Apishapa Arch Las Animas 10151 Herlick Canyon
South Fork Tunnel South Fork Tunnel Pitkin 11519 Mount Champion
Bagley Tunnel Bagley Tunnel San Juan 11427 Handies Peak
Henderson Tunnel Henderson Tunnel Grand 10065 Ute Peak
Pole Hill Tunnel Pole Hill Tunnel Larimer 8717 Panorama Peak
Olympus Tunnel Olympus Tunnel Larimer 8504 Glen Haven
Alva B Adams Tunnel Alva B Adams Tunnel Grand 11447 McHenrys Peak
Saint Vrain Supply Tunnel Saint Vrain Supply Tunnel Boulder 5571 Lyons
Missouri Tunnel Missouri Tunnel Eagle 11276 Mount of the Holy Cross
Hoosier Pass Tunnel Hoosier Pass Tunnel Summit 11653 Alma
Chapman Tunnel Chapman Tunnel Pitkin 11683 Nast
Charles H Boustead Tunnel Charles H Boustead Tunnel Pitkin 11821 Homestake Reservoir
Ivanhoe Tunnel Ivanhoe Tunnel Pitkin 12073 Homestake Reservoir
Moffat Tunnel Moffat Tunnel Grand 11270 East Portal
August P Gumlick Tunnel August P Gumlick Tunnel Clear Creek 11827 Byers Peak
Gunnison Tunnel Gunnison Tunnel Montrose 7047 Cerro Summit
Old Alpine Tunnel (historical) Old Alpine Tunnel (historical) Chaffee 11939 Cumberland Pass
Blanco Tunnel Blanco Tunnel Archuleta 9655 Harris Lake
Tunnel Number 1 Tunnel Number 1 Jefferson 6148 Evergreen
Tunnel Number 2 Tunnel Number 2 Jefferson 6834 Evergreen
Tunnel Number 3 Tunnel Number 3 Jefferson 6722 Evergreen