List of Interstate Highways in Colorado

Interstate Highways in Colorado
Standard highway markers for Interstate 70, Interstate 225, and Interstate 76 Business
Highway names
Interstates	Interstate X (I-X)
Business routes:	Interstate X Business (I-X Bus.)
System links
Colorado State Highways Interstate U.S. State Scenic

Mainline highways

Number	Length (mi)	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
I-25	305.04	490.91	I-25 at the New Mexico state line	I-25 at the Wyoming state line	1958	current
I-70	449.51	723.42	I-70 at the Utah state line	I-70 at the Kansas state line	1956	current
I-76	183.99	296.10	I-70 in Arvada	I-76 at the Nebraska state line	1976	current
I-80S	178.22	286.82	I-25/US 87 in North Washington	I-80S at the Nebraska state line	1958	1976	Renumbered as I-76 to conform to AASHTO policy against suffixed routes
I-225	11.99	19.30	I-25 in Denver	I-70 in Aurora and Denver	1976	current
I-270	5.35	8.61	I-25/US 36 in unincorporated Adams County	I-70 in Denver	1965	current
I-425	5.35	8.61	I-25/US 36 in unincorporated Adams County	I-70 in Denver	—	1959	Original designation for I-270
I-470	—	—	Beltway around Denver		1968	—	Proposed, but cancelled due to environmental concerns
Former

Business routes

Number	Length (mi)	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
I-25 BL	0.5	0.8	Trinidad		—	2009	A 2009 reconstruction project along I-25 rebuilt the northern terminus and eliminated the original exit which removed the route.[1]
I-25 BS	1.94	3.12	Aguilar		—	—
I-25 BL	3.94	6.34	Walsenburg		—	—
I-25 BL	6.75	10.86	Colorado Springs		—	2007
I-25 BL	1.2	1.9	Castle Rock		—	1996	Likely unsigned[2]
I-70 BL	13.36	21.50	Grand Junction	Clifton	—	—
I-70 BL	3.7	6.0	Palisade		—	—
I-70 BL	4.0	6.4	Rifle		—	2004
I-70 BL	0.17	0.27	Silt		—	—	Unsigned
I-70 BL	0.27	0.43	Eagle		—	—	Unsigned
I-70 BL	0.52	0.84	Edwards		—	—	Unsigned
I-70 BL	0.43	0.69	Avon		—	1999
I-70 BL	2.3	3.7	Frisco		—	—
I-70 BL	2.54	4.09	Idaho Springs		—	—
I-70 BL	26.80	43.13	West Pleasant View	Aurora	—	—	Also serves Lakewood and Denver
I-70 BL	0.31	0.50	Watkins		—	—	Only signed along I-70[3]
I-70 BL	0.30	0.48	Strasburg		—	—	Unsigned
I-70 BL	0.31	0.50	Deer Trail		—	—	Unsigned
I-70 BL	0.30	0.48	Agate		—	—	Unsigned
I-70 BL	2.80	4.51	Limon		—	—
I-70 BL	0.51	0.82	Vona		—	—	Unsigned
I-70 BL	1.80	2.90	Burlington		—	—	Only signed along I-70
I-76 BL	0.30	0.48	Keenesburg		—	—	Unsigned
I-76 BL	52.31	84.18	Fort Morgan	Sterling	—	—	Also serves Brush, Hillrose, Merino, and Atwood
Former

See also

•  Colorado portal
•  U.S. Roads portal

References

1. https://www.interstate-guide.com/business/ir-025/
2. https://www.interstate-guide.com/business/ir-025/
3. https://www.interstate-guide.com/business/ir-070/

External links

• Colorado Department of Transportation website
  • Colorado Highway Data
  • Colorado Highway Maps
• The Highways of Colorado by Matthew Salek