US Interstate Map

Q: What is the longest Interstate Highway in the United States?

Interstate 90, or I-90, is the longest Interstate Highway in the United States. It stretches approximately 3,020 miles, or 4,860 kilometers, from Seattle, Washington, to Boston, Massachusetts. Passing through 13 states, I-90 connects major cities and serves as a vital route for travelers, commuters, and commercial transportation across the northern United States.

Q: What is the shortest Interstate Highway in the United States?

Interstate 878, or I-878, in Queens, New York, is the shortest Interstate Highway in the United States. Measuring only about 0.70 miles, or 1.13 kilometers, in length, it serves as a connector between major roadways near John F. Kennedy International Airport. Despite its short distance, it is officially part of the Interstate Highway System.

Q: What is the busiest Interstate Highway in the United States?

Interstate 95, or I-95, is widely recognized as the busiest Interstate Highway in the United States. Stretching from Florida to Maine along the East Coast, it passes through many of the nation’s largest metropolitan areas, including Miami, Jacksonville, Washington, D.C., Baltimore, Philadelphia, New York City, and Boston. As one of the country’s primary transportation corridors, I-95 carries millions of passenger and commercial vehicles each year.

The US Interstate Map is designed for educational and reference purposes displays geographic boundaries and key locations in a clear manner, helpful for spatial understanding, planning, and reference purposes. This US Interstate Map can be accessed offline by downloading it via the button below the map.

US Interstate Map HD US Interstate Map PDF

About US Interstate Map

This US interstate map shows all the interstate highways across the United States, with each route marked by its respective shield. The cities connected by these interstate highways are also displayed on the map. International borders with Canada and Mexico are clearly indicated, and the national capital, Washington, DC, is marked as well. Alaska and Hawaii are shown as inset maps on the USA interstate map.

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 roads that connect America are really something special - they're some of the best in the world. The Interstate Highways system is like the country's backbone, helping people and goods get where they need to go quickly and easily. It's designed for fast, long trips, and it links up all the big cities, which is great for businesses and people who need to travel. Because the roads are all built to the same standards, and you can get on and off them in controlled areas, it makes it really easy to get around. Whether you're driving to work every day or taking a road trip across the country, these highways are essential. They're a big part of daily life in America, and it's hard to imagine how people would get around without them.

History and Development of the Interstate Highway System

The Interstate Highway System was formalized in 1956 when Congress passed the Federal-Aid Highway Act. The legislation was spearheaded by then-President Dwight D. Eisenhower, who saw the potential for the new system of highways to unite America and boost commerce. The Interstate Highway System was inspired by the famous German Autobahn, which Ike traveled during World War II as a military commander. He remembered the efficient roads and was relying on them when he became President. The Interstate Highway System was crucial to the military defense of the country and would help fuel economic growth.

The Interstate Highway System was proposed in the late 1950s and authorized in 1956 to be completed in 10 years at 41,000 miles. It was finally completed at 47,000 miles of Interstate Highways with grade-separated interchanges. It is arguably one of the greatest public works projects to ever hit this country and is still a critical component of our countries’ infrastructure today.

Structure and Numbering System of US Interstates

The Interstate Highway System follows a very logical numbering system. The primary routes are given a one- or two-digit number, and those traveling across the country will know exactly what route they are on. East–west routes have even numbers, and higher even numbers are in the northern states and lower even numbers in the southern states. North–south routes have odd numbers, and the numbers increase from west to east.

In addition to the major cross-country routes and highways like Interstate 10 (I10) from California to Florida and the Eastern seaboard from Seattle to Boston on Interstate 90 (I90), many auxiliary routes with three digit numbers like local bypasses where the parent route passes through city centers, spurs to shopping centers or industrial parks, and connectors to neighboring towns and cities.

Key Features and Design Standards

US Interstate Highways are constructed to meet federal criteria in terms of safety, efficiency and durability. All Interstate Highways are constructed as controlled-access facilities (CFAs) which means that CFAs have no traffic signals, intersections or direct access to Proprietied Facilities. Access to the Interstate system is provided via ramps and interchanges.

Interstates are larger multi-lane highways with more lanes in each direction (typically 2-8) and often wide shoulders and a median divider. Speed limits on Interstates are usually 65-75 mph but are as low as 55 mph in Massachusetts. Interstates are the safest highways for travelers and usually have the most consistent traffic flow.

Economic Importance of the Interstate Highway System

The Interstate system is an essential component of the US economy. It is the backbone for long distance transport of goods. It is used by a number of industries such as trucking and logistics companies, retailers, and manufacturers.

Interstate highways represent approximately one-quarter of total vehicle miles traveled in the United States, for less than 1 percent of the total miles of roads. The Interstate system is a high-capacity multimodal transportation system that supports both commercial and passenger vehicle traffic. It is crucial to our economic growth and development, by reducing travel time and transportation costs allowing for greater productivity.

Connectivity and Major Urban Links

The Interstate Highway System is distinctive in that it generally runs between large metropolitan areas. While roads like I-95 run past the faces of cities like New York and Los Angeles, roads like I-90 will pass right by the outskirts of cities like Chicago and Houston.

While Interstates serve to connect cities and metropolitan areas across the country, they also extend into rural regions that could experience development as a result of the highways. Many of the Interstates provide access to international borders with Canada and Mexico, boosting trade and travel between the two countries.

Maintenance, Modernization, and Challenges

The Interstate Highway System was a powerful and economical solution to create a dynamic, resilient and flexible transportation system for our nation. After nearly sixty years, many sections of the system are old and distressed, traffic congestion in urban areas has reached a crisis, and maintenance and repairs have become an insoluble and costly burden. Rebuilding, restoration or modernization of some sections of the Interstate Highway System may be necessary to address the traffic increases due to more trucks and other vehicles.

Federal and state funds are being used not only to resurface roads and rebuild intersections but also to include intelligent transportation systems and create a greener transportation system to reduce emissions and create a more efficient system of transportation management.

FAQs about US Interstate Highways

What is the Interstate Highway System?

The Interstate Highway System is a nationwide network of controlled-access highways that connects major cities, states, and regions across the United States. Established in 1956 through the Federal-Aid Highway Act, the system was designed to improve transportation, strengthen national defense, and support economic growth. Today, it spans more than 48,000 miles, making it one of the largest and most important highway networks in the world.

What is the longest Interstate Highway in the United States?

Interstate 90 (I-90) is the longest Interstate Highway in the United States. It stretches approximately 3,020 miles (4,860 km) from Seattle, Washington, to Boston, Massachusetts. Passing through 13 states, I-90 connects major cities and serves as a vital route for travelers, commuters, and commercial transportation across the northern United States.

What is the shortest Interstate Highway in the United States?

Interstate 878 (I-878) in Queens, New York, is the shortest Interstate Highway in the United States. Measuring only about 0.70 miles (1.13 km) in length, it serves as a connector between major roadways near John F. Kennedy International Airport. Despite its short distance, it is officially part of the Interstate Highway System.

How are Interstate Highway numbers assigned?

The Interstate Highway System follows a standardized numbering system to help drivers navigate the country. Even-numbered Interstate Highways generally run east to west, with route numbers increasing from south to north, while odd-numbered Interstates run north to south, with numbers increasing from west to east. Three-digit Interstate numbers identify auxiliary routes connected to a primary Interstate, with even first digits usually indicating loops or bypasses and odd first digits indicating spur routes leading into cities or other destinations.

What is the speed limit on Interstate Highways?

Speed limits on Interstate Highways vary depending on state laws, road conditions, and whether the highway passes through urban or rural areas. Most Interstate speed limits range between 55 mph and 80 mph (89–129 km/h). Rural Interstate highways in states such as Texas, Utah, Montana, and Wyoming often have higher speed limits, while urban sections generally have lower limits to improve traffic safety.

What is the busiest Interstate Highway in the United States?

Interstate 95 (I-95) is widely recognized as the busiest Interstate Highway in the United States. Stretching from Florida to Maine along the East Coast, it passes through many of the nation’s largest metropolitan areas, including Miami, Jacksonville, Washington, D.C., Baltimore, Philadelphia, New York City, and Boston. As one of the country’s primary transportation corridors, I-95 carries millions of passenger and commercial vehicles each year.