Interstate 25 in Colorado

Interstate 25 Main route of the Interstate Highway System
Maintained by Colorado Department of Transportation
Length:	305.040 mi[1] (490.914 km)
South end:	I-25 / US 85 / US 87 at New Mexico state line
Major junctions:	US 50 in Pueblo US 24 in Colorado Springs US 36 in Denver US 40 in Denver I-70 in Denver I-76 near Denver US 6 near Denver US 34 near Loveland
North end:	I-25 / US 87 at Wyoming state line
Colorado State Highways < US 24 SH 26 >

In the U.S. state of Colorado, Interstate 25 follows the north-south corridor through Colorado Springs and Denver. It replaced U.S. Highway 87 and most of U.S. Highway 85 for through traffic.

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 description

New Mexico state line to Pueblo

I-25 swerves near the east side of Trinidad Lake State Park.

Following the Santa Fe Trail from New Mexico, Interstate 25 enters Colorado as a typical two-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 Pueblo Lake State Park, home of the Pueblo Lake, which is located to the west of the western city limits of Pueblo.^[6]

Pueblo to Denver

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 National Park in Pueblo. 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 used by NORAD.

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 National Park as well as the entrance to Fort Carson. At exit 135, Academy Boulevard serves Pikes Peak Community College's Centennial campus. By the time I-25 reaches exit 138, the route enters the city limits of Colorado Springs, where the 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 again by exit 141. Exit 142 serves downtown Colorado Springs,^[5] and to the north of the city lies the Colorado College, and is served at exit 143 - Uintah Street. After leaving Colorado Springs, I-25 enters the United States Air Force Academy from exits 150 to 156, and goes through the east side of the territory.

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 the county line at exit 163. I-25 then continues north through more rural areas east of the Rocky Mountains until reaching Castle Rock at exit 181. I-25 continues through a variety of suburban communities 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 interchanges with I-225, a spur that detours motorists to I-70, at exit 200. I-25, then goes around in a general northwest direction before interchanging with US 6 at exit 209. Then 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 213 right before leaving the City and County of Denver. ^[6]

Denver to Wyoming state line

As I-25 leaves Denver, the route continues up north 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 and exit 220, I-25 slips its way through a narrow path between the Badding Reservoir (west side) and the Croke Lake (east side).

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 passes through a medley of lakes and reservoirs to the east and north of Fort Collins.^[5] Afterwards, the interstate gradually makes a north-northeast turn as it heads for the Wyoming state line.^[6]

History

Ancestors and early freeways

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. 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 completion

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 total of 299 miles (481 km) from New Mexico north to Wyoming.^[3][7]

Modern expansion

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)

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 Metro 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.^[8][9]

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.^[9]

COSMIX (Colorado Springs)

COSMIX Logo

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. 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.^[10]

The major goals of COSMIX, which began in 2005 and was completed during 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).^[11]

Though CDOT's role in COSMIX was complete, the City of Colorado Springs continued its own independent project to rebuild the Cimarron Street (US 24) bridge and interchange. This work was functionally complete (allowing limited traffic) by May 2008, with full completion achieved by September 2008.^[12]

Future

Since 2006, the Colorado Department of Transportation has begun work toward expanding the I-25 corridor between Colorado Springs and Denver, as well as the corridor between Denver and the city of Fort Collins (the "North Forty" project, in reference to the 40 miles (64 km) of highway north of Denver that are affected). In both cases, growth of suburbs and smaller communities (such as Castle Rock and Longmont) have necessitated expansion much like that of T-REX or COSMIX (though on a less ambitious scale).^[13][14]

Reconstruction of the aging Trinidad Segment is also underway, aimed mainly at rebuilding bridges and upgrading the highway to modern Interstate design standards. Construction began with demolition and reconstruction of the bridges during 2007, and the remaining viaduct reconstruction is currently scheduled to be completed by August 2009.^[15]

A New Pueblo Freeway project is in the planning stages. Currently, the draft includes an expansion to six lanes (three each direction), numerous interchange improvements, and enhancements to pedestrian routes and public parks along the corridor. Public review of the final plan is scheduled for the Fall of 2008.^[16]

Exit list

County	Location	Mile[1]	#	Destinations	Notes
Las Animas		2.134	2	Wootton
		5.597	6	Gallinas
		7.529	8	Springcreek
		11.013	11	Santa Fe Trail – Starkville
	Trinidad	13.000	13A	Santa Fe Trail
		13.311	13B	Main Street (SH 12 west)
		13.606	14A	SH 12 west – Cuchara, La Veta	Removed (now signed via exit 13B)
		13.606	14B	I-25 Bus. – Trinidad
		14.859	15	US 160 east (Kit Carson Trail)	South end of US 160 overlap
		17.728	18	El Moro Road
		22.906	23	Hoehne Road
		26.858	27	Ludlow
		30.464	30	Aguilar Road
		34.090	34	Aguilar (I-25 Bus. west)
Huerfano		40.485	41	Rugby Road
		41.930	42	Pryor
	Walsenburg	49.000	49	I-25 Bus. north to US 160 west – Walsenburg, Alamosa
		50.054	50	SH 10 east (US 160 west) – La Junta	North end of US 160 overlap
		52.321	52	I-25 Bus. south / SH 69 west to US 160 west – Gardner, Westcliffe, Walsenburg, Alamosa
		55.000	55	Airport Road
		56.000	56	Redrock Road
		58.727	59	Butte Road
		60.084	60	Huerfano
		64.046	64	Lascar Road
		66.749	67	Apache
Pueblo		71.264	71	Graneros Road
		74.367	74	SH 165 west – San Isabel, Colorado City, Rye
		77.267	77	Abbey Road, Hatchet Ranch Road
		83.461	83	(unnamed road)
		86.938	87	Verde Road
		87.921	88	Burnt Mill Road
		90.625	91	Stem Beach
	Pueblo	94.769	94	SH 45 north (Pueblo Boulevard)
		95.901	96	Minnequa Avenue, Indiana Avenue
		96.673	97A	Central Avenue
		97.447	97B	Abriendo Avenue
		97.691	98A	US 50 Bus. east – La Junta
		98.545	98B	To SH 96 / 1st Street
		98.806	99A	To SH 96 / 6th Street	Southbound exit and northbound entrance
		99.334	99B	13th Street, Santa Fe Avenue
		99.950	100A	US 50 east – La Junta, Pueblo Memorial Airport	South end of US 50 overlap
		100.681	100B	29th Street
		101.389	101	US 50 west (SH 47 east) – Canon City, Royal Gorge	North end of US 50 overlap
		102.160	102	Eagleridge Boulevard
		103.896	104	Eden
		106.075	106	Porter Draw
		108.000	108	Purcell Boulevard – Pueblo West
		110.238	110	Pinon
		114.000	114	Young Hollow
		115.831	116	County Line Road
El Paso		118.843	119	Rancho Colorado Boulevard
		121.459	122	Pikes Peak International Raceway
		123.189	123	(unnamed road)
	Fountain	124.564	125	Ray Nixon Road
		127.860	128	US 85 north – Fountain	North end of US 85 overlap
		131.653	132	SH 16 (Mesa Ridge Parkway) – Fort Carson, Fountain
	Security-Widefield	135.262	135	SH 83 (Academy Boulevard)
	Colorado Springs	137.752	138	SH 29 (Circle Drive)
		138.742	139	US 24 east – Limon	South end of US 24 overlap
		139.747- 139.869	140	I-25 Bus. north / US 85 (Nevada Avenue) to SH 115 south / Tejon Street
		141.139	141	US 24 west (Cimarron Street) – Manitou Springs, Pikes Peak	North end of US 24 overlap
		141.849	142	Bijou Street – Downtown Colorado Springs
		142.832	143	Uintah Street
		143.520	144	Fontanero Street
		144.622	145	SH 38 east (Fillmore Street)
		146.074	146	Garden of the Gods Road
		147.046	147	Rockrimmon Boulevard
		147.570	148A	I-25 Bus. south (Nevada Avenue, US 85 south)	South end of US 85 overlap; no southbound entrance
			148B	Corporate Centre Drive	Southbound exit and entrance
		148.830	149	Woodmen Road
		150.303	150	To SH 83 / Academy Boulevard
		151.660	151	Briargate Parkway
		152.899	153	Interquest Parkway
		155.930	156A	Gleneagle Drive
	Air Force Academy	155.930	156B	North Entrance Air Force Academy
	Monument	158.199	158	Baptist Road
		160.763	161	SH 105 – Palmer Lake, Monument
		163.321	163	County Line Road – Palmer Lake
Douglas
		167.464	167	Greenland
		171.820	172	Upper Lake Gulch Road
		172.307	173	Larkspur	Southbound exit and northbound entrance
		173.791	174	Tomah Road
	Castle Rock	180.808	181	Wilcox Street, Plum Creek Parkway
		181.853	182	Wilcox Street, Wolfensberger Road
		184.212	184	US 85 north (Meadows Parkway) / SH 86 east / Founders Parkway	North end of US 85 overlap
		186.935	187	Happy Canyon Road
		188.486	188	Castle Pines Parkway
		189.756	190	Surrey Ridge
		191.412	191	(unnamed road)
	Lone Tree	192.096	192	RidgeGate Parkway	Opened in May 2009
		192.990	193	Lincoln Avenue
		194.314	194	SH 470 west / E-470 east – Grand Junction, Limon
		195.130	195	County Line Road
Arapahoe	Centennial
		196.141	196	Dry Creek Road
	Greenwood Village	197.188	197	SH 88 east (Arapahoe Road)	South end of SH 88 overlap
		198.292	198	Orchard Road
		199.384	199	SH 88 west (Belleview Avenue)	North end of SH 88 overlap
Denver	Denver	200.093	200	I-225 north to I-70 – Limon, Aurora
		201.578	201	US 285 / SH 30 (Hampden Avenue)
		202.640	202	Yale Avenue
		203.537	203	Evans Avenue
		204.037	204	SH 2 (Colorado Boulevard)
		205.057	205	University Boulevard
		205.919	206	Downing Street	Northbound exit and southbound entrance
		206.149- 206.341	206	Washington Street, Emerson Street	Southbound exit and northbound entrance
		206.968	207A	Lincoln Street, Broadway
		207.488	207B	US 85 south (Santa Fe Drive)	South end of US 85 overlap
		207.641- 207.990	208	SH 26 (Alameda Avenue)	Northbound exit is via exit 207B
		209.210	209A	6th Avenue east
		209.210	209B	US 6 west (6th Avenue) – Lakewood	South end of US 6 overlap
		209.479	209C	8th Avenue
		210.310	210A	US 40 (Colfax Avenue, I-70 Bus./US 287) – Downtown Denver
		210.415	210C	SH 33 (Auraria Parkway)	Northbound exit and southbound entrance
		210.532	210B	17th Avenue	Southbound exit (to 20th Avenue) is via exit 211
		211.109	211	23rd Avenue
		211.464	212	Speer Boulevard – Downtown Denver	Signed as exits 212A (south) and 212B (north)
		212.096	212C	20th Street
		212.769	213	Park Avenue, West 38th Avenue
		213.625- 213.739	214A	I-70 (US 6 east/US 85 north) – Limon, Grand Junction	North end of US 6 / US 85 overlap
Adams		213.964	214B	48th Avenue	Southbound exit only
		215.244	215	SH 58 (58th Avenue)
		216.301- 216.397	216	I-76 – Grand Junction, Fort Morgan, Aurora	Signed as exits 216A (east) and 216B (west)
		216.779	216B	70th Avenue (SH 224)	Northbound exit and southbound entrance
		217.006	217A	US 36 west – Westminster, Boulder	Signed as exit 217 northbound
		217.006	217B	I-270 east – Limon, Aurora	Southbound exit and northbound entrance
	Thornton	218.463	219	84th Avenue – Federal Heights
		219.815	220	Thornton Parkway
	Northglenn	221.027	221	104th Avenue – Northglenn	Former SH 44
		223.049	223	SH 128 west (120th Avenue)
	Thornton, Westminster
		225.000	225	136th Avenue
		226.085	226	144th Avenue
Adams, Broomfield	Thornton, Broomfield	227.745	228	E-470 / Northwest Parkway – Limon, Broomfield
		229.107	229	SH 7 – Lafayette, Brighton
Broomfield	Broomfield
		232.094	232	Dacono, Erie
Weld
		235.114	235	SH 52 – Dacono, Frederick, Fort Lupton
	Dacono
		240.114	240	SH 119 west – Firestone, Longmont
		243.148	243	SH 66 – Longmont, Lyons
	Mead	245.217	245	Mead
	Johnstown	250.241	250	SH 56 west – Berthoud
		252.261	252	SH 60 east – Johnstown, Milliken
Larimer		254.216	254	To SH 60 west – Campion	Exit ramps only
		255.272	255	SH 402 west – Loveland
		257.305	257	US 34 – Greeley, Loveland	Signed as exits 257A (east) and 257B (west)
	Loveland	259.309	259	Crossroads Boulevard Fort Collins-Loveland Airport
		262.298	262	SH 392 east – Windsor
	Fort Collins	265.314	265	SH 68 west (Harmony Road)
		268.475	268	Prospect Road
		269.370	269	SH 14 – Ault, Fort Collins	Signed as exits 269A (east) and 269B (west)
		271.373	271	Mountain Vista Drive
		277.884	278	SH 1 south – Wellington
		281.338	281	Owl Canyon Road
		287.550	288	Buckeye Road
Weld		292.583	293	Carr

References

External links

• Colorado Department of Transportation (CDOT)
• COSMIX (CDOT project; website no longer being updated)
• South I-25 Corridor: Lincoln Avenue through Castle Rock (CDOT project)
• The North Forty (CDOT project)
• I-25 Trinidad (CDOT project)
• The New Pueblo Freeway (proposed CDOT project)

Interstate 25
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