List of Interstate Highways

Source: Wikipedia, the free encyclopedia.

Dwight D. Eisenhower National System of Interstate and Defense Highways

Interstate 90 marker

Eisenhower Interstate System sign
Highway shield for Interstate 90 and the Eisenhower Interstate System
Map
Primary Interstate Highways in the 48 contiguous states as of 2022
System information
FormedJune 29, 1956[1]
Highway names
InterstatesInterstate X (I-X)
System links

There are 70 primary Interstate Highways in the

freeways in the United States. These primary highways are assigned one- or two-digit route numbers, whereas their associated auxiliary Interstate Highways receive three-digit route numbers. Typically, odd-numbered Interstates run south–north, with lower numbers in the west and higher numbers in the east; even-numbered Interstates run west–east, with lower numbers in the south and higher numbers in the north. Route numbers divisible by 5 usually represent major coast-to-coast or border-to-border routes (ex. I-10 connects Santa Monica, California to Jacksonville, Florida
, extending between the Pacific and Atlantic oceans). Auxiliary highways have an added digit prefixing the number of the parent highway.

Five route numbers are duplicated in the system; the corresponding highways are in different regions, reducing potential confusion. In addition to primary highways in the contiguous United States, there are signed Interstates in Hawaii and unsigned Interstates in Alaska and Puerto Rico.

Contiguous United States

There are 70 primary interstate highways in the 48 contiguous United States as well as five former and one future primary interstate highways. This number does not include auxiliary Interstate Highways.

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
I-2 46.80 75.32 BL US 83 in Peñitas, Texas I-69E/US 77/US 83 in Harlingen, Texas 02013-01-012013 current Unfinished in Texas
Texas only
I-4 132.30 212.92 I-275 in Tampa, Florida 01959-01-011959 current Florida only
I-5 1381.29 2,222.97
Mexican border in San Ysidro, California
Hwy 99 at Canadian border in Blaine, Washington 01956-01-011956 current Serves three states:
I-8 348.25 560.45 Sunset Cliffs Boulevard/Nimitz Boulevard in
San Diego, California
I-10 in Casa Grande, Arizona 01964-01-011964 current Serves two states: California, Arizona
I-10 2460.34 3,959.53 SR 1 in Santa Monica, California I-95/US 17/SR 15/SR 228 in Jacksonville, Florida 01957-01-011957 current Serves eight states:
I-910
I-11 22.60 36.37 US 93 at Arizona state line near Boulder City, Nevada 02017-01-012017 current Unfinished in Nevada
Nevada only; planned in one more: Arizona
I-12 85.59 137.74 I-10 in Baton Rouge, Louisiana I-10/I-59 in Slidell, Louisiana 01967-01-011967 current Louisiana only
I-14 25.10 40.39 US 190/US 190 Bus in Copperas Cove, Texas I-35/US 190 in Belton, Texas 02017-01-262017 current Unfinished in Texas
Texas only; planned in four more: Louisiana, Mississippi, Alabama, Georgia
Planned associated routes:
I-214
in Texas
I-15 1433.52 2,307.03
San Diego, California
Sweetgrass, Montana
01957-01-011957 current Unfinished in California
Serves six states:
I-315, I-515
I-16 166.81 268.45
SR 540 in Macon, Georgia
Montgomery Street in Savannah, Georgia 01966-01-011966 current Georgia only
Associated route: I-516
I-17 145.76 234.58 I-10/US 60 in Phoenix, Arizona I-40/SR 89A in Flagstaff, Arizona 01961-01-011961 current Arizona only
I-19 63.35 101.95 I-19 Bus. in Nogales, Arizona I-10 in Tucson, Arizona 01972-01-011972 current Arizona only
Uses kilometers instead of miles
I-20 1539.38 2,477.39 I-10 at Scroggins Draw, Texas 01957-01-011957 current Serves six states: Texas, Louisiana, Mississippi, Alabama, Georgia, South Carolina
Associated routes: I-220, I-520, I-820
I-22 202.22 325.44 I-269/US 78/MS 304 near Byhalia, Mississippi I-65 in Birmingham, Alabama 02012-01-012012 current Unfinished in Alabama
Serves two states: Mississippi, Alabama
Planned associated routes:
I-422
in Alabama
I-24 316.36 509.13
Pulley's Mill, Illinois
I-75 in Chattanooga, Tennessee 01962-01-011962 current Serves four states: Illinois, Kentucky, Tennessee, Georgia
Associated route: I-124
I-25 1061.67 1,708.59 I-10/US 85/US 180 in Las Cruces, New Mexico I-90/US 87 in Buffalo, Wyoming 01957-01-011957 current Serves three states: New Mexico, Colorado, Wyoming
Associated route: I-225
I-26 304.64 490.27 US 17 in Charleston, South Carolina 01960-01-011960 current Unfinished in North Carolina
Serves three states:
Tennessee, North Carolina, South Carolina
Associated routes: I-126, I-526
I-27 124.13 199.77 US 87/Loop 289 in Lubbock, Texas I-40/US 87/US 287/US 60 in Amarillo, Texas 01969-01-011969 current Unfinished in Texas
Texas only; planned in one more: New Mexico
I-29 755.51 1,215.88 I-35/I-70/US 24/US 40/US 71 in Kansas City, Missouri US 81 and PTH 75 at Canadian border in Pembina, North Dakota 01958-01-011958 current Serves four states: Missouri, Iowa, South Dakota, North Dakota
Associated routes: I-129, I-229
I-30 366.76 590.24 I-20 in Fort Worth, Texas I-40/US 65/US 67/US 167 in North Little Rock, Arkansas 01957-01-011957 current Serves two states: Texas, Arkansas
Associated routes: I-430, I-530, I-630
I-31
I-94 in Fargo, North Dakota US 81 and PTH 75 at Canadian border in Pembina, North Dakota 01957-01-011957 01958-01-011958 Served North Dakota only
Replaced by a northward extension of I-29
I-35 1568.38 2,524.06 US 83/Victoria Street in Laredo, Texas
LSCT/26th Avenue in Duluth, Minnesota
01956-01-011956 current Serves six states: Texas, Oklahoma, Kansas, Missouri, Iowa, Minnesota
Associated routes: I-35E, I-35W, I-135, I-235, I-335, I-435, I-535, I-635
I-37 143.00 230.14 US 181 in Corpus Christi, Texas
San Antonio, Texas
01959-01-011959 current Texas only
I-39 306.14 492.68 I-55 in Normal, Illinois WIS 29/US 51 in Wausau, Wisconsin 01984-01-011984 current Serves two states: Illinois, Wisconsin
I-40 2556.61 4,114.46 I-15 in Barstow, California US 117/NC 132 in Wilmington, North Carolina 01964-01-011964 current Serves eight states: California, Arizona, New Mexico, Texas, Oklahoma, Arkansas, Tennessee, North Carolina
Associated routes: I-140, I-240, I-440, I-540, I-640, I-840
I-41 175.00 281.64 I-94/US 41 in Russell, Illinois I-43/US 41/US 141 in Howard, Wisconsin 02015-01-012015 current Serves two states: Illinois, Wisconsin
I-42
142.00 228.53 I-40/US 70 in Garner, North Carolina US 70 in Morehead City, North Carolina proposed Future Interstate, will only serve North Carolina
I-43 191.55 308.27 I-39/I-90 in Beloit, Wisconsin I-41/US 41/US 141 in Howard, Wisconsin 01981-01-011981 current Wisconsin only
I-44 636.69 1,024.65 US 82/US 277/US 281/US 287 in Wichita Falls, Texas
St. Louis, Missouri
01958-01-011958 current Serves three states:
I-344 in Oklahoma
I-45 284.91 458.52 SH 87 in Galveston, Texas
Dallas, Texas
01971-01-011971 current Texas only
Associated route: I-345
I-49 528.02 849.77 I-10/US 167/LA 182 in Lafayette, Louisiana I-435/I-470/US 50/US 71 in Kansas City, Missouri 01984-01-011984 current Unfinished in Arkansas and Louisiana
Serves three states: Louisiana, Arkansas, Missouri; planned in one more: Texas
I-55 964.25 1,551.81 I-10 in LaPlace, Louisiana
Chicago, Illinois
01960-01-011960 current Serves six states: Louisiana, Mississippi, Tennessee, Arkansas, Missouri, Illinois
Associated routes: I-155, I-255, I-355, I-555
I-57 386.12 621.40 I-55 in Miner, Missouri
Chicago, Illinois
01965-01-011965 current Unfinished in Missouri
Serves two states: Missouri, Illinois; planned in one more: Arkansas
I-59 445.23 716.53 I-10/I-12 in Slidell, Louisiana I-24 in Wildwood, Georgia 01960-01-011960 current Serves four states: Louisiana, Mississippi, Alabama, Georgia
Associated routes: I-359, I-459, I-759
I-64 963.52 1,550.64 I-70/US 61 in Wentzville, Missouri I-264/I-664 in Chesapeake, Virginia 01961-01-011961 current Serves six states: Missouri, Illinois, Indiana, Kentucky, West Virginia, Virginia
Associated routes: I-264, I-464, I-564, I-664
I-65 887.30 1,427.97 I-10 in Mobile, Alabama US 12/US 20 in Gary, Indiana 01958-01-011958 current Serves four states: Alabama, Tennessee, Kentucky, Indiana
Associated routes: I-165, I-265, I-465, I-565, I-865; Planned: I-365 in Kentucky
I-66
Witchita, Kansas
Near Pikeville, Kentucky 01991-01-011991 02015-01-012015[3] Served four states: Kansas, Missouri, Illinois, Kentucky
Associated routes: I-66 Spur in Kentucky
The project was unpopular and ultimately cancelled without the interstate being completed; I-66 Spur eventually became I-165
I-66 76.28 122.76 I-81 in Front Royal, Virginia US 29 in Washington, D.C. 01961-01-011961 current Serves DC and one state: Virginia
I-68 113.15 182.10 I-79 in Morgantown, West Virginia I-70 in Hancock, Maryland 01991-01-011991 current Serves two states: West Virginia, Maryland
I-69 879.82 1,415.93 US 59 in Rosenberg, Texas Hwy 402 at Canadian border in Port Huron, Michigan 01957-01-011957 current Unfinished in Texas, Mississippi, Kentucky, and Indiana
Serves six states: Texas, Mississippi, Kentucky, Indiana, Michigan. Planned/started in 3 more: Louisiana, Arkansas, Tennessee
Associated routes: I-69C, I-69E, I-69W, I-169, I-269, I-369, I-469; Planned: I-569 in Kentucky
I-70 2172.16 3,495.75
Cove Fort, Utah
I-695 in Woodlawn, Maryland 01956-01-011956 current Serves 10 states: Utah, Colorado, Kansas, Missouri, Illinois, Indiana, Ohio, West Virginia, Pennsylvania, Maryland
Associated routes: I-170, I-270, I-370, I-470, I-670
I-71 345.57 556.14 I-64 in Louisville, Kentucky
Cleveland, Ohio
01959-01-011959 current Serves two states: Kentucky, Ohio
Associated routes: I-271, I-471
I-72 179.29 288.54 US 61 in Hannibal, Missouri Church Street and University Avenue in Champaign, Illinois 01970-01-011970 current Serves two states: Missouri, Illinois
Associated route: I-172
I-73 99.43 160.02 US 220 near Stokesdale, North Carolina I‑74 and US 220 in Randleman, North Carolina 01997-01-011997 current Unfinished in North Carolina
North Carolina only; planned in five more: South Carolina, Virginia, West Virginia, Ohio, Michigan
I-74 491.74 791.38 I-80 in Bettendorf, Iowa US 74/NC 41 near Lumberton, North Carolina 01974-01-011974 current Unfinished in Ohio and North Carolina
Serves five states: Iowa, Illinois, Indiana, Ohio, North Carolina; planned in three more: West Virginia, Virginia, South Carolina
Associated routes: I-474; Planned: I-274 in North Carolina
I-75 1786.47 2,875.04 SR 826/SR 916/SR 924 in Miami Lakes, Florida Canadian border at Sault Ste. Marie, Michigan 01958-01-011958 current Serves six states: Florida, Georgia, Tennessee, Kentucky, Ohio, Michigan
Associated routes: I-175, I-275, I-375, I-475, I-575, I-675
I-76 186.48 300.11
Denver, Colorado
I-80 at Big Springs, Nebraska 01975-01-011975 current Serves two states: Colorado, Nebraska
I-76 435.66 701.13 I-71 in Westfield Center, Ohio 01964-01-011964 current Serves three states:
I-276, I-376, I-476, I-676
I-77 610.10 981.86 I-26 in Columbia, South Carolina
Cleveland, Ohio
01958-01-011958 current Serves five states: South Carolina, North Carolina, Virginia, West Virginia, Ohio
Associated route: I-277
I-78 146.28 235.41 I-81 at Jonestown, Pennsylvania Canal Street in New York City 01957-01-011957 current Serves three states:
I-878
I-79 343.46 552.75 I-77 in Charleston, West Virginia PA 5 in Erie, Pennsylvania 01967-01-011967 current Serves two states: West Virginia, Pennsylvania
Associated routes: I-279, I-579
I-80 2899.59 4,666.44 US 101 in San Francisco, California I-95 in Teaneck, New Jersey 01956-01-011956 current Serves 11 states:
I-81 855.02 1,376.02 I-40 in Dandridge, Tennessee Hwy 137 at Canadian border on Wellesley Island, New York 01961-01-011961 current Serves six states:
I-381, I-481, I-581, I-781
I-82 143.58 231.07 I-90 in Ellensburg, Washington 01957-01-011957 current Serves two states: Washington, Oregon
Associated route: I-182
I-82 I-95 in Teaneck, New Jersey 01957-01-011957 01958-01-011958 Served two states: Pennsylvania, New Jersey
Was the initial designation to what is now I-380 and I-80
I-82
Providence, Rhode Island 01956-01-011956 01968-01-011968 Served one state: Connecticut, was planned for one state: Rhode Island
Redesignated as I-84 in 1968
I-83 85.03 136.84 President Street and Fayette Street in
Baltimore, Maryland
I-81 in Harrisburg, Pennsylvania 01959-01-011959 current Serves two states: Maryland, Pennsylvania
Associated route: I-283
I-84 769.62 1,238.58 I-5 in Portland, Oregon I-80 in Echo, Utah 01980-01-011980 current Serves three states: Oregon, Idaho, Utah
Associated route: I-184
I-84 232.71 374.51 I-81 in Scranton, Pennsylvania I-90 in Sturbridge, Massachusetts 01963-01-011963 current Serves four states: Pennsylvania, New York, Connecticut, Massachusetts
Associated routes: I-384, I-684
I-85 666.05 1,071.90 I-65 in Montgomery, Alabama I-95 in Petersburg, Virginia 01958-01-011958 current Unfinished in Alabama
Serves five states:
North Carolina
I-86 62.85 101.15
I-84 near Declo, Idaho
I-15 in Chubbuck, Idaho 01980-01-011980 current Idaho only
I-86 223.39 359.51 I-90 near North East, Pennsylvania NY 17/NY 79 in Windsor, New York 01999-01-011999 current Unfinished in New York
Serves two states: Pennsylvania, New York
I-86
38.97 62.72 I-90 in Sturbridge, Massachusetts 01968-01-011968 01984-01-011984 Served two states: Connecticut, Massachusetts
Redesignated as I-84 in 1984 when the I-84 Hartford-Providence corridor was cancelled
I-87 12.90 20.76 I-440/US 64/US 264 in Raleigh, North Carolina US 64/US 264 in Wendell, North Carolina 02017-01-012017 current Unfinished in North Carolina
North Carolina only; planned in one more: Virginia
Associated route: I-587
Shortest Interstate highway in contiguous United States
I-87 333.49 536.70 I-278 in New York City A-15 at Canadian border in Champlain, New York 01957-01-011957 current New York only
Associated routes:
I-587, I-787
I-88 140.60 226.27 I-80/IL 92 in East Moline, Illinois 01987-01-011987 current Illinois only
I-88 117.75 189.50 I-81 in Binghamton, New York I-90 in Schenectady, New York 01968-01-011968 current New York only
I-89 191.12 307.58 I-93/SR 3A in Bow, New Hampshire Route 133/Future A-35 at Canadian border in Highgate, Vermont 01960-01-011960 current Serves two states: New Hampshire, Vermont
Associated route: I-189
I-90 3020.44 4,860.93
Seattle, Washington
Boston, Massachusetts
01956-01-011956 current Serves 13 states:
Massachusetts
Associated routes: I-190, I-290, I-390, I-490, I-590, I-690, I-790, I-890, I-990

Longest Interstate highway
I-91 290.37 467.31 I-95/Route 34 in New Haven, Connecticut A-55 at Canadian border in Derby Line, Vermont 01958-01-011958 current Serves three states: Connecticut, Massachusetts, Vermont
Associated routes: I-291, I-391, I-691
I-93 189.95 305.69 I-95/US 1 in Canton, Massachusetts I-91 in St. Johnsbury, Vermont 01957-01-011957 current Serves three states:
Vermont
Associated routes: I-293, I-393
I-94 1585.20 2,551.13 I-90 in Lockwood, Montana Highway 402 at Canadian border in Port Huron, Michigan 01956-01-011956 current Serves seven states: Montana, North Dakota, Minnesota, Wisconsin, Illinois, Indiana, Michigan
Associated routes: I-194, I-294, I-394, I-494, I-694, I-794, I-894
I-95 1919.31 3,088.83
Miami, Florida
NB 95 at Canadian border in Houlton, Maine 01957-01-011957 current Serves DC and 15 states: Florida, Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, New Jersey, New York, Connecticut, Rhode Island, Massachusetts, New Hampshire, Maine
Associated routes: I-195, I-295, I-395, I-495, I-595, I-695, I-795, I-895
Longest primary north-south Interstate highway
I-96 192.06 309.09 US 31 in Norton Shores, Michigan I-75 in Detroit, Michigan 01959-01-011959 current Michigan only
Associated routes: I-196, I-296, I-496, I-696
I-97 17.62 28.36 US 50 in Annapolis, Maryland 01987-01-011987 current Maryland only
I-99 98.34 158.26 01998-01-011998 current Unfinished in Pennsylvania
Serves two states: Pennsylvania, New York
  •       Former
  •       Proposed and unbuilt

Other regions

In addition to the 48 contiguous states, Interstate Highways are found in Hawaii, Alaska, and Puerto Rico. The Federal Highway Administration funds four routes in Alaska and three routes in Puerto Rico under the same program as the rest of the Interstate Highway System. However, these routes are not required to meet the same standards as the mainland routes:

Highways on the Interstate System in Alaska and Puerto Rico shall be designed in accordance with such geometric and construction standards as are adequate for current and probable future traffic demands and the needs of the locality of the highway.[4]

Hawaii

Map
Map of Hawaii's Interstate Highways (excluding H-201)

The Interstate Highways on the island of Oʻahu, Hawaii are signed with the standard Interstate Highway shield, with the letter "H-" prefixed before the number. They are fully controlled-access routes built to the same standards as the mainland Interstate Highways.

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
H-1 27.16 43.71 Route 93 in Kapolei Route 72 in Honolulu 01960-01-011960 current Associated route: H-201
H-2 8.33 13.41 H-1 in Pearl City
Route 99 in Wahiawa
01960-01-011960 current
H-3 15.32 24.66 H-1/H-201 in Halawa Marine Corps Base Hawaii 01997-01-011997 current

Alaska

Map
Map of Alaska's Interstate Highways

Alaska's Interstate Highways are unsigned as such, although they all have state highway numbers that do not match the Interstate Highway numbers.[5]

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
A-1
408.23 656.98 Anchorage Canadian border in Alcan Border 01976-01-011976 current
A-2
202.18 325.38 Tok Fairbanks 01976-01-011976 current Alaska Highway, Richardson Highway[7][8][9]
A-3
148.12 238.38 Anchorage Soldotna 01976-01-011976 current Seward Highway, Sterling Highway[6][8][9]
A-4
323.69 520.93 Gateway, near Palmer Fairbanks 01976-01-011976 current Parks Highway[6][7][8][9]

Puerto Rico

Map of the Interstates in Puerto Rico

freeway-standard toll roads.[10]

Number Length (mi)[2] Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
PR-1 71.08 114.39 PR-2 in Ponce PR-2 in San Juan 01976-01-011976 current Follows PR-52
PR-2 138.13 222.30 PR-1 in Ponce PR-3 in San Juan 01976-01-011976 current Follows PR-22
PR-3 40.56 65.27 PR-3 in Humacao PR-2 in San Juan 01976-01-011976 current Follows PR-66

See also


References

  1. ^ Weingroff, Richard F. (Summer 1996). "Federal-Aid Highway Act of 1956, Creating the Interstate System". Public Roads. 60 (1). Washington, DC: Federal Highway Administration. Retrieved March 16, 2012.
  2. ^ a b c d "Table 1: Main Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways as of December 31, 2018". FHWA Route Log and Finder List. Federal Highway Administration. May 6, 2019. Retrieved April 21, 2021.
  3. ^ Nelsen, Carrie (July 9, 2015). "For Immediate Release" (PDF) (Press release). Illinois Department of Transportation. Archived from the original (PDF) on September 6, 2015.
  4. ^ Staff. "FHWA Route Log and Finder List". Federal Highway Administration. Retrieved May 24, 2007.
  5. ^ Voss, Oscar. "Alaska Roads: Interstate ends photos". Retrieved May 24, 2007.
  6. ^ a b c Witt, Jennifer W. (2010). Annual Traffic Volume Report (PDF) (Report) (2008-2009-2010 ed.). Alaska Department of Transportation & Public Facilities. Archived from the original (PDF) on March 30, 2014. Retrieved March 15, 2012.
  7. ^ a b c Birkholz, Ethan (2010). Annual Traffic Volume Report (PDF) (Report) (2008-2009-2010 ed.). Alaska Department of Transportation & Public Facilities. Archived from the original (PDF) on April 17, 2014. Retrieved May 31, 2012.
  8. ^ a b c d Staff. "Dwight D. Eisenhower Interstate Routes Statewide" (PDF). Federal Highway Administration. Retrieved May 31, 2012.
  9. ^ a b c d Staff. "Alaska Department of Transportation and Public Facilities Routes by Description: CDS Route Numbers as of 28 October 2008" (PDF). Federal Highway Administration. Retrieved May 31, 2012.
  10. ^ Voss, Oscar. "Puerto Rico road photos". Retrieved May 24, 2007.

External links