List of Interstate Highways in Iowa

70px Highway markers for I-29, I-680, and I-35 Bus. Loop
System information
Formed:	August 14, 1957
Highway names
Interstates:	Interstate X (I-X)
Business Loops:	Interstate X Business (I-X Bus.)
System links
Iowa Primary Highway System Interstate U.S. State Secondary Scenic

Interstate Highways in Iowa form a network of freeways that cross the state.

Primary Interstates

Number	Length (mi)	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
I0029 !I‑29	151.826	244.340	I-29 at Hamburg	I-29 at Sioux City	1958	current	All of I-29 is part of the Lewis & Clark Trail; completed in 1972
I0035 !I‑35	218.432	351.532	I-35 near Lamoni	I-35 near Albert Lea, Minn.	1958	current
I0074 !I‑74	5.386	8.668	I-80 at Davenport	I-74 / US 6 at Bettendorf	1968	current
I0080 !I‑80	306.268	492.891	I-80 at Council Bluffs	I-80 at LeClaire	1958	current	I-80 is the longest Interstate Highway in Iowa; completed in 1972

• Primary Interstates
• 

  I-29 crossing over the mouth of the Floyd River

• 

  I-35 approaching exit 182

• IA 5 interchange from I-35.JPG

  Exit 68 to Iowa Highway 5 on I-35 south of West Des Moines

• I-74 bridge toward Bettendorf.JPG

  The Interstate 74 Bridge carrying I-74 across the Mississippi River

• 

  I-80 in western Iowa near Walnut

• Iowa Flood I-80 DSM 20080613.jpg

  Traffic congestion on I‑35 / I‑80 during the Iowa flood of 2008

Auxiliary Interstates

Number	Length (mi)	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
x25px I0080-1 !I‑80N	16.565	26.659	I-29 at Loveland	I-80 near Neola	1966	1973	Now the eastern end of I-680, I-80N was a spur from Loveland to Neola
I0129 !I‑129	0.286	0.460	I-129 / US 20 / US 75 at Sioux City	I-29 / US 20 / US 75 at Sioux City	1976	current
I0235 !I‑235	13.816	22.235	I-35 / I-80 at West Des Moines	I-35 / I-80 at Des Moines	1961	current
I0280 !I‑280	9.581	15.419	I-80 / US 6 at Davenport	I-280 at Rock Island, Ill.	1973	current
I0380 !I‑380	73.080	117.611	I-80 / US 218 / Iowa 27 near Coralville	US 218 at Waterloo	1973	current
I0480 !I‑480	0.721	1.160	I-480 / US 6 at Council Bluffs	I-29 / US 6 at Council Bluffs	1966	current
I0680 !I‑680	29.391	47.300	I-680 at Omaha, Nebr.	I-80 near Neola	1966	current
Former

• Auxiliary Interstates
• I-235 Des Moines.JPG

  I‑235 crossing the Des Moines River in Des Moines, Iowa

• I235 keynote bridge.jpg

  The Edna M. Griffin Memorial Bridge carrying I‑235 across the Des Moines River

• 

  The I‑480 bridge over the Missouri River between Council Bluffs, Iowa and Downtown Omaha, Nebraska

• I-280 Bridge.jpg

  I‑280 crosses the Mississippi River over the Baker Bridge.

Business routes

Number	Length (mi)	Length (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	Notes
BL0035 !I‑35 Business Loop	—	—	I-35 / US 30 in Ames	I-35 in Ames	—	—	Serves Ames
BL0035 !I‑35 Business Loop	—	—	I-35 / US 18 in Clear Lake	I-35 / US 18 / Iowa 122 in Clear Lake	—	—	Serves Clear Lake

External links

• The Iowa Highways Page by Jason Hancock
• Interstate Guide