Interstate 25 in Colorado

In the U.S. state of Colorado, Interstate 25 (I-25) follows the north–south corridor through Colorado Springs and Denver. The highway enters the state from the north near Carr and exits the state near Starkville. The highway also runs through the cities of Fort Collins, Loveland, and Pueblo. The route is concurrent with U.S. Highway 87 through the entire length of the state. I-25 replaced U.S. Highway 87 and most of U.S. Highway 85 for through traffic.

Interstate 25 marker

Interstate 25
U.S. Route 87
I-25 and US 87 highlighted in red
Route information
Maintained by CDOT
Length298.87 mi[1] (480.98 km)
Major junctions
South end I-25 / US 85 / US 87 near Trinidad
North end I-25 / US 87 near Wellington
CountiesLas Animas, Huerfano, Pueblo, El Paso, Douglas, Arapahoe, Denver, Adams, Broomfield, Weld, Larimer
Highway system
Colorado State Highways
US 24.svg US 24I-25Colorado 26.svg SH 26
Colorado 86.svg SH 86US 87Colorado 88.svg SH 88

Historical nicknames for this route have included the Valley Highway (through Denver), Monument Valley Highway (through Colorado Springs), and the Pueblo Freeway (through Pueblo). Within El Paso County, the route has been dedicated as the Ronald Reagan Highway.[2][3] In Pueblo County, the route is called John F. Kennedy Memorial Highway.

Interstate 25 is also considered to be part of the unofficial Pan-American Highway.[4]

Route descriptionEdit

New Mexico state line to PuebloEdit

Northbound I-25 between Colorado Springs and Denver.

Following the Santa Fe Trail from New Mexico, Interstate 25 enters Colorado as a typical four-lane Interstate Highway, where its entire route in Colorado lies close to the east side of the Rocky Mountains. The route turns from north to west-northwest as I-25 serves Wootton. After leaving Wootton, I-25 turns back up north and bypasses near the east side of the Trinidad Lake State Park, home of the Trinidad Lake.

Trinidad, a city near the Trinidad Lake, is the first major city that lies along I-25. For the next 30 miles (48 km), I-25 continues north through the rural areas of Colorado until it reaches the small city of Walsenburg, where the business route - I-25 Bus. - junctions with U.S. Highway 160. I-25 then continues in a north-northwest direction until it bypasses the Orlando Reservoir, then turns north from there until it reaches Colorado City. In Colorado City, I-25 interchanges with the east end of the Frontier Pathways Scenic and Historic Byway (SH 165) at exit 74.

After leaving the city, I-25 follows in a north-northeast orientation until it reaches the St. Charles Reservoir just before entering the city of Pueblo, with the first exit within the southern city limits of Pueblo at exit 94.[5] The Arkansas River in Pueblo serves as a feeder to the Lake Pueblo State Park, home of the Pueblo Lake, which is located to the west of the western city limits of Pueblo.[6]

Pueblo to DenverEdit

I-25 during rush hour in the largest city I-25 serves, Denver, looking East toward Downtown Denver.

After leaving Pueblo, I-25 continues up north with the Union Pacific Railroad line paralleling closely to the route on the right side after interchanging with Porter Draw at exit 106. By exit 119, the Fountain Creek joins along and travels parallel with I-25, and continues all the way to the Fountain Creek Regional Park in Widefield. I-25 gradually turns from a general north direction to the north-northwest and serves the census-designated place of Buttes at exit 122.

Cheyenne Mountain, as seen from I-25 near Fort Carson. Note the communications antennas at the summit, which are radio antennas for stations broadcasting in Colorado Springs.

As soon as US 85 leaves I-25 at exit 128, I-25 enters the city limits of Fountain. Basically, I-25 serves as the border between the western city limits of Fountain on the east side of I-25 and Fort Carson on the west side. Exit 132 (SH 16) serves the north side of the Fountain Creek Regional Park as well as the entrance to Fort Carson and connects to SH 21 (Powers Boulevard), the eastern bypass for the Colorado Springs metro area. By the time I-25 reaches exit 138, the route crosses into the city limits of Colorado Springs, where the stack interchange with US 24 at exit 139 serves the Evergreen Cemetery and Prospect Lake. I-25 turns west at exit 140, along with the Fountain Creek, where it interchanges with US 85, US 87, and I-25 Bus. I-25 again turns back north by exit 141. Swinging around the west side of downtown Colorado Springs at exit 142,[5] and to the north of the city lies the Colorado College, and is served at exit 143 - Uintah Street. Continuing north and northeast, the highway intersects the north terminus of I-25 Bus. and US 85. The interstate leaves Colorado Springs between exits 153 and 156, where I-25 enters the United States Air Force Academy, going through the east side of the institution.

Map showing I-25 and nearby freeways and major highways in the Denver Metropolitan area

I-25 leaves El Paso County and enters Douglas County at Monument Hill, elevation 7,352 feet, north of Monument. I-25 then continues north through more rural and hilly areas east of the Rocky Mountains until reaching Castle Rock at exit 181. I-25 continues through rural and hilly portions of Douglas County until interchanging with E-470, the partial beltway of Denver as the toll road serves the Centennial Airport and the much larger Denver International Airport.

After entering Arapahoe County, I-25 cuts through the Denver Technological Center (DTC) between Dry Creek Road and Belleview Avenue (exits 196-199). I-25 enters Denver at the I-225 interchange, a spur that detours motorists to I-70 through Aurora, at exit 200. I-25 turns in an westerly direction between Evans Avenue (Exit 203) and Colorado Boulevard (Exit 204). University of Denver lies just to the south of the interstate at Exit 205. It then turns back north after Exit 207. I-25 curves around the west side of downtown Denver,[5] where it can be accessed by I-70 Bus. at exit 210.[5] I-25 then interchanges with I-70 at exit 214 right before leaving the City and County of Denver. [6]

Denver to Wyoming state lineEdit

As I-25 leaves Denver, the route continues up north through unincorporated areas of Adams County and interchanges with I-76, I-270, and the Denver-Boulder Turnpike (US 36). Due to the complexity of this triangle-shaped interchange, it was known to be one of many malfunction junctions throughout the United States. Beyond that interchange, the interstate enters the northern suburbs of the Denver metro area, such as Thornton and Northglenn, and at exit 220, I-25 slips its way through a narrow path between the Badding Reservoir (west side) and the Croke Lake (east side). Development begins to drop off after exit 223 (120th Avenue) after continuing north into Westminster and eastern Broomfield.

At exit 228, I-25 interchanges with the northern termini of E-470 and Northwest Parkway at a stack interchange, with the Larkridge Mall just to the north, served by 160th Avenue (SH 7). As I-25 continues north, it moves through rolling farm and grasslands with the Front Range and high mountains clearly visible to the west while passing through a medley of lakes and reservoirs. It stays generally flat with few moderate climbs in elevation, while also serving smaller cities like Dacono and Firestone to the east and Longmont to the west. This stretch of I-25 in northern Colorado also has large amounts of truck traffic between SH 7 and Wyoming. After some time in the rural farmlands, the interstate enters the Fort Collins/Loveland metro area at exit 255, serving Loveland and Greeley to at exits 255 and 257, Windsor at exit 261, and continuing north to the Fort Collins city limits south of Harmony Road. The highway runs on the eastern side of Fort Collins, serving Colorado State University at exits 268 and 269 (which is also the most direct route to downtown). After exit 271, I-25 leaves Fort Collins and rolls into more rural grasslands past Wellington. Exits also become few and far between from here to Wyoming as well after gradually turning north-easterly towards the state line.[5][6]


Ancestors and early freewaysEdit

Colorado had begun planning of a modern inter-city route along the Front Range as early as 1944, well before the national movement toward an Interstate Highway system.

State Highway 1, an unpaved road, was completed between Denver and Pueblo by 1919. Average travel time between Pueblo and Colorado Springs on this route was approximately 2.5 hours (or a full 8.5 hours from Pueblo to Denver). This route was upgraded with the help of the federal government to become US 85 and US 87 by 1930, now paved in concrete and shortening the travel time between Pueblo and Colorado Springs to just one hour.

The cities of Denver (in 1948) and Pueblo (in 1949) were first to begin building multi-lane highway segments along the route of what would eventually become Interstate 25. Construction follows an earlier segment of the Colorado and Southern Railway. Denver's segment was originally known as the Valley Highway and was completed by 1958. The city of Colorado Springs followed a similar theme with their Monument Valley Freeway, begun in 1955 and completed by July 1960. Pueblo's section — the Pueblo Freeway - was complete by July 1959.[3]

Interstate completionEdit

As the national Interstate Highway System began to take shape, actual "inter-state" connections began to be made. Wyoming came first in 1964, building a 9-mile (14 km) link north to Cheyenne that was connected to Colorado's 17-mile (27 km) stretch.

Linking to New Mexico in the south would prove more problematic as the planned route had to stretch over Raton Pass, and its accompanying 1,800-foot (550 m) elevation change, within just 13 miles (21 km). Once again, US 85 and US 87 were used, but it had to be re-graded in places to meet Interstate design guidelines. Construction began in 1960, with a link to the city of Trinidad completed by 1963. The Trinidad Segment (as CDOT now calls the Raton Pass span) was not fully completed until 1968.

The final segment of the Colorado portion of Interstate 25, connecting the cities of Walsenburg and Trinidad, was completed during 1969. This meant that four lanes of high-speed, nonstop freeway were finally open for a full 305 miles (491 km) from New Mexico north to Wyoming.[3][7]

Modern expansionEdit

As both population and traffic increased in Colorado during the 1990s and 2000s, the Colorado Department of Transportation has planned and completed major improvements for the city corridors along I-25.

T-REX (Denver)Edit

T-REX Logo

The first of these was Transportation Expansion (T-REX), which widened and expanded nearly 17 miles (27 km) of both I-25 and the I-225 bypass in the Denver Metropolitan Area as well as adding various pedestrian and aesthetic improvements. T-REX was also instrumental in expanding Denver's RTD light rail lines to connect outlying communities beyond the city and county of Denver, adding 19 miles (31 km) of new routes.[7][8]

Starting in early 2004, the T-REX project was completed during 2006 at a cost of US$1.67 billion, under its projected budget and two years ahead of its originally scheduled conclusion. It has been hailed as a "model for other cities to follow" and "ahead of the curve nationally" by federal transportation and transit authorities.[8]

COSMIX (Colorado Springs)Edit


As T-REX began to wrap up, CDOT's next major effort began with Colorado Springs Metro Interstate Expansion (COSMIX). It could be argued that COSMIX was even more important to Colorado's interests than T-REX had been, since the Colorado Springs corridor of I-25 had seen immense growth over the past four decades, and experienced major choke points all along the 16-mile corridor from Exit 135 (Academy Blvd) in the south to Exit 151 (Briargate Pkwy) in the north. Originally carrying around 8500 vehicles per day in 1960, usage of the former Monument Valley Freeway had grown to an average of 100,000 vehicles per day by 2005.[9]

The major goals of COSMIX, which began in 2005 and was completed a year and four days ahead of schedule at the very end of December 2007, were a general expansion and widening of the corridor to three lanes in each direction throughout the city, as well as the reconstruction of two main interchanges (at Bijou Street near downtown Colorado Springs, and at Rockrimmon Boulevard and North Nevada Avenue in the city's growing north side).[10] Originally estimated at $225 million, on delivery COSMIX cost only $150 million, approximately $20 million of which involved land acquisition costs.

COSMIX was the first funded portion of a larger plan for I-25 improvements as detailed in an Environmental Assessment approved by CDOT and FHWA in 2004. A second phase resulted in the widening of the 12 mile segment from Woodmen Road (exit 149) to Monument (exit 161) to six lanes and addition of auxiliary lanes at busy interchanges. The Air Force Academy interchange (exit 156) was reconfigured to include just one exit, instead of A/B, and features two new roundabouts for North Gate Boulevard. The widening and paving was completed in December 2014.[11]

An EA-recommended improvement not included in COSMIX due to funding limitations was the reconstruction of the I-25 interchange at Cimarron Street (US 24 West). CDOT completed this project in late 2017.


As of October 2020, a seven mile segment of I-25 through Pueblo is currently under construction. Enhancements include the widening of two bridges, noise wall installation, the softening of curves for better safety, and the addition of acceleration and deceleration lanes.[12] The $69 million dollar project was expected to finish in Spring 2019.[13]

There is much controversy surrounding the future of Interstate 25 in northern Colorado (SH 7 in Broomfield to SH 14 in Fort Collins). Suggestions from adding toll lanes to general expansion to six lanes from the two lane bottleneck at SH 66 to SH 14 and adding multi-modal transportation options have been discussed. The future of the highway remains in question as funding is limited, and agreement is limited as well. The I-25 corridor in Weld and Larimer counties is becoming increasingly heavy with traffic, and something will have to be done soon.[14]

In Colorado Springs, SH 21 (Powers Blvd.) is currently getting extended past SH 83 to its official northern terminus at I-25. This project provides an easier bypass around the north end of the town and will also help connect Voyager Pkwy traffic to the interstate. The construction is in two phases, I-25 is involved in phase 1 where a new directional T-interchange (Y-interchange) will be built near exit 156 at N. Gate Blvd. between mile markers 149 and 151. As of October 2020, phase 1 of the construction is underway and is anticipated to be completed in summer 2021.[15][16]

The Gap is an 18-mile stretch of Interstate 25 from south of Castle Rock to Monument, in both Douglas and El Paso counties. It is the only four-lane section of I-25, connecting Colorado's two largest cities, Denver and Colorado Springs. Over the years, congestion, crashes and delays have grown due to population growth and more people using the road. Efforts to improve these conditions are underway and the project is slated to be completed in 2022 with a cost of $350 million, with contributions from Douglas and El Paso counties, Pikes Peak Rural Transportation Authority and a federal INFRA grant.[citation needed]

Exit listEdit

ColoradoNew Mexico line0.0000.000  I-25 south (US 85 / US 87 south) – Santa Fe, AlbuquerqueContinuation into New Mexico
460Truck weigh stationNorthbound entrance extends into Colorado; exit number is based on New Mexico mileage
Las Animas2.1343.4342Wootton
Trinidad11.01317.72411Santa Fe Trail – Starkville
13.00020.92113AVan Buren StreetNorthbound exit and southbound entrance
13.31121.42213B  SH 12 west (Main Street) – Cuchara, La Veta, Springfield
13.90622.38014Commercial Street
14.85923.91315   US 160 east (Kit Carson Trail) to SH 239 north / Goddard AvenueSouth end of US 160 overlap
17.72828.53018El Moro Road
22.90636.86423Hoehne Road
30.46449.02730Aguilar Road (I-25 BL north)
34.09054.86334  I-25 BL south – Aguilar
Huerfano40.48565.15441Rugby Road
Walsenburg49.00078.85849   I-25 BL north to US 160 west – Walsenburg, Alamosa
50.05480.55450  US 160 west (Fifth Street) / SH 10 east – La JuntaNorth end of US 160 overlap
52.32184.20252   I-25 BL south to US 160 west – Walsenburg, Alamosa
55.00088.51455Airport Road
56.00090.12356Redrock Road
58.72794.51259Butte Road
64.046103.07264Lascar Road
PuebloColorado City71.264114.68871Graneros Road
74.367119.68274  SH 165 west – Colorado City, Rye, San Isabel
77.267124.34977Abbey Road, Hatchet Ranch Road
86.938139.91387Verde Road
87.921141.49588Burnt Mill Road
90.625145.84791Stem Beach
Pueblo94.769152.51694  SH 45 north (Pueblo Boulevard)
95.403153.53695Illinois AvenueSouthbound exit only
95.901154.33896Minnequa Avenue, Indiana AvenueSouthbound exit to Minnequa Ave., one block north of Indiana Ave.; Northbound exit to and entrance from Indiana Ave.; Southbound entrance from Aqua Ave., one block south of Indiana Ave.
96.673155.58097ACentral Avenue to Northern Avenue
97.447156.82697BAbriendo Avenue
  US 50 Bus. – La Junta
98.545158.59398B  To SH 96 / 1st Street
98.806159.01399A  To SH 96 / 6th StreetSouthbound exit and northbound entrance (from Bradford Avenue)
  US 50 Bus. east (13th Street, Santa Fe Avenue)
South end of US 50 Bus. overlap
    US 50 east / US 50 Bus. – La Junta, Pueblo Memorial Airport
South end of US 50 overlap; western terminus of US 50 Bus.
100.681162.030100B29th Street
101.389163.170101   US 50 west / SH 47 east – Cañon CityNorth end of US 50 overlap
102.160164.411102Eagleridge Boulevard
106.075170.711106Porter Draw
108.000173.809108Purcell Boulevard – Pueblo West
114.000183.465114Young Hollow
115.831186.412116County Line Road
El Paso118.843191.259119Rancho Colorado Boulevard
Fountain121.459195.469122Pikes Peak International Raceway
123.189198.253123Clear Spring RanchExit does not sign this destination
124.564200.466125Ray Nixon Road
127.860205.771128  US 85 north – FountainNorth end of US 85 overlap
131.653211.875132   SH 16 east (Mesa Ridge Parkway) to SH 21 – Fort Carson Gate 20Signed as exits 132A (SH 16) and 132B (Ft. Carson) southbound
Stratmoor135.262217.683135  South Academy Boulevard – Colorado Springs Airport
Colorado Springs137.752221.690138Lake Avenue, Circle Drive
138.742223.284139  US 24 east (Martin Luther King Jr. Bypass) – LimonSouth end of US 24 overlap
140  SH 115 south (Nevada Avenue, Tejon Street) – Cañon City
141.139227.141141  US 24 west (Cimarron Street) – Manitou Springs, Pikes PeakNorth end of US 24 overlap
141.849228.284142Bijou Street – Downtown Colorado Springs
142.832229.866143Uintah Street
143.520230.973144Fontanero Street
144.622232.747145Fillmore StreetDiverging diamond interchange
146.074235.083146Garden of the Gods Road
148Nevada Avenue (US 85 south), Corporate Drive, Rockrimmon BoulevardSouth end of US 85 overlap
148.830239.519149Woodmen Road
150.303241.889150North Academy Boulevard
151.660244.073151Briargate Parkway
152.899246.067153  To SH 21 (Powers Boulevard) / InterQuest Parkway – Black Forest
  SH 21 (Powers Boulevard) – Colorado SpringsFuture interchange[17]
Air Force Academy155.930250.945156North Gate Boulevard – North Entrance Air Force Academy
158.199254.597158Baptist Road
Monument160.763258.723161  SH 105 – Monument, Palmer Lake
El PasoDouglas
county line
163.321262.840163County Line Road – Palmer Lake
171.820276.517172Upper Lake Gulch Road
172.307277.301173LarkspurSouthbound exit and northbound entrance; access via former SH 18
173.791279.690174Tomah Road
Castle RockCrystal Valley ParkwayFuture interchange[18]
180.808290.982181Plum Creek Parkway
181.853292.664182Wilcox Street, Wolfensberger Road
184.212296.460184   US 85 north (Meadows Parkway) / SH 86 east (Founders Parkway)North end of US 85 overlap
Castle Pines186.935300.843187Happy Canyon Road
188.486303.339188Castle Pines Parkway
Lone Tree192.096309.149192RidgeGate ParkwayOpened on May 20, 2009[19]
192.990310.587193Lincoln Avenue
194.314312.718194   SH 470 west / E-470 east – Grand Junction, LimonE-470 exit 1 westbound; SH-470 exit 26 eastbound
county line
Lone TreeCentennial line195.130314.031195County Line Road
ArapahoeCentennial196.141315.658196Dry Creek Road
197.188317.343197  SH 88 east (Arapahoe Road)South end of SH 88 overlap
Greenwood Village198.292319.120198Orchard Road
199.384320.877199  SH 88 west (Belleview Avenue)North end of SH 88 overlap
City and County of Denver200.093322.018200   I-225 north to I-70 – Limon, AuroraI-225 exits 1A-B southbound; tri-stack interchange.
201.578324.408201   US 285 south / SH 30 east (Hampden Avenue)
202.640326.117202Yale Avenue
203.537327.561203Evans Avenue
204.037328.366204  SH 2 (Colorado Boulevard)
205.057330.007205University Boulevard
205.919331.395206Downing Street, Washington Street, Emerson StreetDowning St. not signed southbound
207ALincoln Street, BroadwayLincoln St. not signed southbound
207BSanta Fe Drive to   SH 26Northbound exit and southbound entrance
  US 85 south (Santa Fe Drive)South end of US 85 overlap; southbound exit and northbound entrance
208  SH 26 (Alameda Avenue)Southbound exit and northbound entrance; northbound access is via exit 207B
209.210336.691209  US 6 west (6th Avenue) – LakewoodSouth end of US 6 overlap; signed as exits 209A (east) and 209B (west)
209.479337.124209C8th Avenue
210.310338.461210A   US 40 / US 287 (Colfax Avenue) – Downtown Denver
210.415338.630210BAuraria ParkwayNorthbound exit and southbound entrance
210.532338.818210C17th AvenueNorthbound exit and entrance; southbound access is via exit 211
211.109339.74721123rd Avenue, 20th Avenue20th Ave. not signed northbound
211.464340.318212A-BSpeer Boulevard – Downtown DenverSigned as exits 212A (south) and 212B (north)
212.096341.335212C20th Street
I-25 HOV/toll lanesSouth end of reversible HOV/toll lanes
19th StreetSouthbound exit and northbound entrance for HOV/toll lanes only
212.769342.419213Park Avenue, West 38th Avenue
214A  I-70 (US 6 east/US 85 north) – Limon, Grand JunctionNorth end of US 6/US 85 overlap; locally known as The Mousetrap; I-70 exit 274
213.964344.342214B48th AvenueSouthbound exit only
AdamsNorth Washington215.244346.40221558th Avenue
216.301348.103216A  I-76 east – Fort MorganNorthbound exit and southbound entrance; I-76 exit 5
216B   SH 224 (70th Avenue) / I-76 west – Grand JunctionSigned as exit 216 southbound; SH 224 not signed southbound; I-76 exit 5
  SH 224 (70th Avenue)Northbound exit and southbound right entrance for HOV/toll lanes only
217.006349.237217   I-270 east / US 36 – Limon, Aurora, Westminster, BoulderNo access to I-270/US 36 east northbound; southbound signed as exits 217A (west) and 217B (east); I-270 exit 0 to I-25 north.
  US 36 west – BoulderSouthbound right exit and northbound entrance for HOV/toll lanes only
I-25 HOV/toll lanesNorth end of reversible HOV/toll lanes
Thornton218.463351.58221984th Avenue – Federal Heights
219.815353.758220Thornton Parkway
Northglenn221.027355.708221104th Avenue – NorthglennFormer SH 44
223.049358.963223  SH 128 west (120th Avenue)
Westminster225.000362.102225136th Avenue
226.085363.849226144th Avenue
City and County of Broomfield227.745366.520228   E-470 east / Northwest Parkway west – Limon, BroomfieldE-470/NW Pkwy. exit 47
229.107368.712229  SH 7 – Lafayette, Brighton
WeldDacono232.094373.519232Dacono, Erie
235.114378.379235  SH 52 – Dacono, Frederick, Fort Lupton
Firestone240.114386.426240  SH 119 west – Firestone, Longmont
Mead243.148391.309243  SH 66 – Longmont, Lyons
Johnstown250.241402.724250  SH 56 west – Berthoud
252.261405.975252  SH 60 east – Johnstown, Milliken
Larimer254.216409.121254  To SH 60 west – Campion
255.272410.820255  SH 402 west – Loveland
Loveland257.305414.092257  US 34 – Greeley, Loveland
259.309417.317259  Crossroads Boulevard – Fort Collins-Loveland Airport
Windsor262.298422.128262  SH 392 – Windsor, Fort Collins
Fort Collins265.314426.981265Harmony Road
268.475432.069268Prospect Road
269A-B  SH 14 – Fort Collins, AultSigned as exits 269A (east) and 269B (west)
271.373436.733271Mountain Vista Drive
Wellington277.884447.211278  SH 1 south – Wellington
281.338452.770281Owl Canyon Road
287.550462.767288Buckeye Road
298.870480.985   I-25 / US 87 north – Cheyenne, CasperContinuation into Wyoming
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

Related routesEdit


Interstate 25 Business

In Colorado, Interstate 25 has one auxiliary route and two active business routes. There was also one other auxiliary interstate and three other business routes that were decommissioned. Interstate 225 is the only active auxiliary route for I-25 that runs from its parent highway from the Denver Tech Center to Interstate 70 north of Aurora. Interstate 425 was a former designation for what is now Interstate 270.[20] Along with I-225, the two active business routes for I-25 run through Aguilar and Walsenburg. The three former routes ran through Trinidad, Colorado Springs, and Castle Rock.


  1. ^ a b Colorado Department of Transportation, Highway Data Archived July 14, 2011, at the Wayback Machine, accessed October 2007: note that not every interval between mileposts is exactly a mile, explaining why more exits than expected are at the exact milepost
  2. ^ Ronald Reagan Presidential Foundation & Library Archived July 25, 2008, at the Wayback Machine
  3. ^ a b c "Interstate 25". Retrieved November 27, 2011.
  4. ^ Sierra County Economic Development Organization. "Transportation and Highways". Archived from the original on September 7, 2007. Retrieved February 2008. Check date values in: |access-date= (help)
  5. ^ a b c d e The Road Atlas (Map). Rand McNally. 2006. p. 32.
  6. ^ a b c Google Maps street maps and USGS topographic maps, accessed February 2008 via ACME Mapper
  7. ^ a b Kuennen, Tom, ed. Interstate 50: 50 Years of the Dwight D. Eisenhower National System of Interstate and Defense Highways. 2006: Faircount. pp 118-119. ISBN unavailable.
  8. ^ a b "Metro Denver's multi-modal T-REX takes last step - Metro Denver Economic Development Corporation". Archived from the original on December 15, 2011. Retrieved November 27, 2011.
  9. ^ Kuennen, Tom, ed. Interstate 50: 50 Years of the Dwight D. Eisenhower National System of Interstate and Defense Highways. 2006: Faircount. pp 118-119. ISBN unavailable.
  10. ^ "Progress of Project". Archived from the original on January 13, 2010. Retrieved November 27, 2011.
  11. ^ "Archived copy". Archived from the original on October 17, 2014. Retrieved October 11, 2014.CS1 maint: archived copy as title (link)
  12. ^ Miguel, Michelle (April 16, 2015). "Construction on I-25 through Pueblo starts this summer". KRDO. Retrieved February 25, 2019.
  13. ^ "SB I-25 to close overnight in Pueblo as part of Ilex project". January 15, 2019. Retrieved February 25, 2019.
  14. ^ "North I-25 (Denver to Wyoming)".
  15. ^ "I-25/Powers Boulevard Interchange: About". Retrieved December 31, 2020.
  16. ^ "CO 21 Research Parkway Interchange Study". Retrieved December 31, 2020.
  17. ^ "I-25 & Powers Boulevard Interchange: About". Archived from the original on September 26, 2020. Retrieved April 6, 2021.
  18. ^ "Crystal Valley Interchange". Castle Rock, CO - Official Website. Town of Castle Rock and its representatives. Retrieved August 2, 2020.
  19. ^ "RidgeGate Parkway Interchange Brings Traffic Relief to Douglas County" (PDF). Southeast Connections. June 2009. Retrieved November 27, 2011.
  20. ^ Summers, Stephen (April 18, 2003). "Interstate Numbering AASHTO and FHWA". news misc.transport.road. Retrieved April 15, 2021.

External linksEdit

Route map:

KML is from Wikidata

  Interstate 25
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New Mexico
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  U.S. Route 87
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New Mexico
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