Explore USA interstate map or US interstate highway map to locate all the interstate highways network of United States.
United States Maps in our Store - Order High Resolution Vector and Raster Files
List of Interstate Highways in the US
S.N.
Interstate Highway Number
Formed
Length in km
Length in mi
1
I-90
1956
4,988.55
3099.74
2
I-80
1956
4,666.44
2899.59
3
I-40
1957
4,114.46
2556.61
4
I-10
1957
3,959.53
2,460.34
5
I-70
1956
3,495.03
2171.71
6
I-95
1957
3,088.83
1919.31
7
I-75
1958
2,875.04
1786.47
8
I-94
1956
2,551.13
1585.2
9
I-35
1956
2,524.06
1568.38
10
I-20
1957
2,477.39
1539.38
11
I-15
1957
2,307.03
1,433.52
12
I-5
1956
2,222.97
1,381.29
13
I-25
1957
1,708.59
1061.67
14
I-55
1960
1,551.81
964.25
15
I-64
1961
1,550.64
963.52
16
I-69
1957
1,464.66
910.1
17
I-65
1958
1,427.97
887.3
18
I-81
1961
1,376.02
855.02
19
I-84
1980
1,238.58
769.62
20
I-29
1958
1,215.88
755.51
21
I-85
1958
1,071.90
666.05
22
I-44
1958
1,024.65
636.69
23
I-77
1958
981.86
610.1
24
I-49
1984
881.15
547.52
25
I-74
1974
871.65
541.62
26
I-57
1965
819.03
508.92
27
I-59
1960
716.53
445.23
28
I-76
1964
701
435.66
29
I-30
1957
590.24
366.76
30
I-8
1964
560.45
348.25
31
I-71
1959
556.14
345.57
32
I-79
1967
552.75
343.46
33
I-87
1957
536.7
333.49
34
I-26
1960
528.01
328.09
35
I-24
1962
509.13
316.36
36
I-39
1984
492.68
306.14
37
I-91
1958
467.31
290.37
38
I-45
1971
458.52
284.91
39
I-86
1999
408.81
254.02
40
I-84
1963
374.51
232.71
41
I-22
2012
325.44
202.22
42
I-96
1959
309.09
192.06
43
I-43
1981
308
191.55
44
I-89
1960
307.58
191.12
45
I-42
proposed
310
190
46
I-93
1957
305.69
189.95
47
I-76
1975
300.11
186.48
48
I-72
1970
288.54
179.29
49
I-41
2015
281.64
175
50
I-16
1966
268.45
166.81
51
I-78
1957
235.41
146.28
52
I-17
1961
234.85
145.93
53
I-82
1957
231.07
143.58
54
I-37
1959
230.14
143
55
I-88
1987
226.27
140.6
56
I-4
1959
212.92
132.30
57
I-27
1969
206.53
128.332
58
I-88
1968
189.5
117.75
59
I-68
1991
182.1
113.15
60
I-73
1997
162.7
101.1
61
I-99
1998
158.26
98.34
62
I-12
1967
137.74
85.59
63
I-83
1959
136.84
85.03
64
I-66
1961
122.76
76.28
65
I-19
1972
101.95
63.35
66
I-86
1980
101.15
62.85
67
I-11
2017
86.74
53.90
68
I-2
2013
75.32
46.8
69
I-42
2024
50.7
31.5
70
I-14
2017
40.39
25.10
71
I-97
1987
28.36
17.62
72
I-87
2017
20.76
12.9
US Interstate Highways
The Dwight D. Eisenhower National System of Interstate and Defense Highways serves as the official name for the Interstate Highway System which functions as the fundamental ground transportation network across the United States. The system extends across every state in the country while supporting both national defense operations and commercial activities and daily travel needs. The system extends 78,465 kilometers across all 50 states making it the world's second-largest national motorway network behind China. The system included features for high-speed travel along with standardized safety features and engineering standards which included grade-separated interchanges and limited access points and consistent signage.
Historical Background
During the early 20th century the Interstate System began its development until President Dwight D. Eisenhower initiated its creation after witnessing Germany's autobahn system during World War II. The strategic value of a strong highway network for military and economic needs led Eisenhower to support the Federal-Aid Highway Act of 1956 which funded the construction of 41,000 miles of interstate highways and allocated $25 billion for the project which became the biggest public works undertaking in U.S. history. The program required an initial 13-year completion timeline but ended up spanning multiple decades because of planning difficulties and funding and construction challenges.
Structure and Numbering System
Travelers can navigate the extensive network through the Interstate System because it uses a well-organized and consistent numbering system. The Interstate System follows a logical numbering system where primary interstates receive one or two digits: East-west routes have even numbers that decrease from south to north (I-10 to I-90) and north-south routes have odd numbers that decrease from west to east (I-5 to I-95). The Interstate System includes two major east-west routes: Interstate 80 connects San Francisco to Teaneck while Interstate 40 connects Barstow to Wilmington. The three-digit number system identifies auxiliary interstates which function as beltways and bypasses and spurs that link urban areas to the primary interstates.
Current Network and Statistics
The Interstate Highway System transports 25% of all vehicle miles across the United States while covering only 1% of public road mileage. The transportation network handles approximately 85 million daily trips which include both personal vehicles and substantial commercial freight movements. The interstates have evolved into multi-lane urban highways with complex interchanges that primarily exist in metropolitan areas including Los Angeles, Chicago, Atlanta and Houston. I-90 stands as the longest interstate highway at 3,020 miles which connects Seattle to Boston while I-878 in Queens New York remains the shortest at 0.7 miles.
Economic and Strategic Importance
The interstate system creates substantial economic effects. The system allows for efficient and dependable good transportation which decreases industrial logistics expenses while enabling time-sensitive delivery systems. The majority of United States freight movements depend on highways and interstates serve as the main transportation routes for these shipments. The network functions as a rapid military deployment system which explains its initial designation as defense infrastructure. The system has driven both suburban development and real estate expansion and regional economic growth since its construction began.
Maintenance, Expansion, and Challenges
The original construction phase of the Interstate System remains mostly finished but the system currently deals with problems from aging infrastructure combined with rising congestion levels and climate resilience needs. The system's bridges together with tunnels and roadbeds have reached or surpassed their planned design lifespan thus triggering nationwide initiatives for corridor rehabilitation and modernization. The Infrastructure Investment and Jobs Act (IIJA) from 2021 dedicated billions of dollars to highway maintenance and expansion which demonstrated federal infrastructure support. Multiple states have initiated trials of smart highway systems and high-occupancy toll lanes and electric vehicle charging infrastructure to ensure their interstate segments remain future-ready.
Future Outlook
The U.S. Interstate Highway System stands as a fundamental and developing part of national mobility for the future. The system will transform to meet 21st-century demands because traffic volumes will increase while autonomous vehicles emerge as new technologies. The next generation of interstate travel takes shape through collaboration between regional planning authorities and the Department of Transportation and private sector partners who focus on safety and efficiency alongside sustainability and resilience in emerging transportation paradigms.
