The Full Wiki

List of Interstate Highways: Wikis


Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.


From Wikipedia, the free encyclopedia

Interstate Highways in the 48 contiguous states. Purple routes are currently built and open freeways, blue are currently open spur routes, and green indicates proposed routes, future roads, or those currently under construction.

Primary Interstate Highways are the major interstate highways of the United States and are assigned a one or two-digit route number. Even route numbers are assigned to east/west routes, with the lower numbered routes being further south (I-10) and higher numbered routes in the north (I-90). Similarly, odd route numbers are assigned to north/south routes, with the lower numbered routes being further west (I-5) and the higher numbered routes being further east (I-95).

There are five pairs of numbers that are duplicated throughout the system; the corresponding highways are separated by large distances to prevent confusion. Below, these are differentiated from each other by West and East.

Three-digit Interstates are spur or loop Interstates that usually service large cities and suburbs. The last two digits of a three-digit Interstate are always the number of the parent route, the primary Interstate where it originated. If the first digit is odd, the Interstate is typically a spur route while if the first digit is even, the Interstate is typically a loop route. Three-digit Interstates are covered in their parent route's article, and those that have their own articles are linked below.


Primary Interstates

There are 66 primary Interstates listed in the table below, with 43 of them having auxiliary routes. Listed lengths are as of October 31, 2002.

Routes ending in 0 or 5 are highlighted in green.

Associated routes (* not signposted as interstates)
 I-4.svg I-4 Tampa, Florida (I-275) to Daytona Beach, Florida (I-95)
Associated routes: none
 I-5.svg I-5 San Ysidro, California (Mexico) to Blaine, Washington (Canada)
Associated routes: I-105, I-205, I-305*, I-405, I-505, I-605, I-705, I-805
 I-8.svg I-8 San Diego, California to Casa Grande, Arizona (I-10)
Associated routes: none
I-10.svg I-10 Santa Monica, California (CA-1) to Jacksonville, Florida (I-95)
Associated routes: I-110, I-210, I-310, I-410, I-510, I-610, I-710, I-910
I-12.svg I-12 Baton Rouge, Louisiana (I-10) to Slidell, Louisiana (I-10)
Associated routes: none
I-15.svg I-15 San Diego, California (CA-15) to Sweetgrass, Montana (Canada)
Associated routes: I-115, I-215, I-315*, I-515
I-16.svg I-16 Macon, Georgia (I-75) to Savannah, Georgia
Associated route: I-516
I-17.svg I-17 Phoenix, Arizona (I-10) to Flagstaff, Arizona (I-40)
Associated routes: none
I-19.svg I-19 Nogales, Arizona (Mexico) to Tucson, Arizona (I-10)
Associated routes: none
I-20.svg I-20 Kent, Texas (I-10) to Florence, South Carolina (I-95)
Associated routes: I-220, I-520, I-820
I-22.svg I-22 Memphis, Tennessee (I-55 & I-40) to Birmingham, Alabama (I-20, I-59 & I-65)
Under construction
I-24.svg I-24 Pulley's Mill, Illinois (I-57) to Chattanooga, Tennessee (I-75)
Associated route: I-124
I-25.svg I-25 Las Cruces, New Mexico (I-10) to Buffalo, Wyoming (I-90)
Associated route: I-225
I-26.svg I-26 Colonial Heights, Tennessee (I-81) to Charleston, South Carolina (US-17)
Associated routes: I-126, I-526
I-27.svg I-27 Lubbock, Texas (US-87) to Amarillo, Texas (I-40)
Associated routes: none
I-29.svg I-29 Kansas City, Missouri (I-35 & I-70) to Pembina, North Dakota (Canada)
Associated routes: I-129, I-229
I-30.svg I-30 Fort Worth, Texas (I-20) to Little Rock, Arkansas (I-40)
Associated routes: I-430, I-530, I-630
I-35.svg I-35 Laredo, Texas (Mexico) to Duluth, Minnesota (MN-61)
Associated routes: I-35E, I-35W, I-135, I-235, I-335, I-435, I-535, I-635
I-37.svg I-37 Corpus Christi, Texas (US-181) to San Antonio, Texas (I-35)
Associated routes: none
I-39.svg I-39 Normal, Illinois (I-55) to Wausau, Wisconsin (WIS 29)
Associated routes: none
I-40.svg I-40 Barstow, California (I-15) to Wilmington, North Carolina (NC-132)
Associated routes: I-140, I-240, I-440, I-540, I-840
I-43.svg I-43 Beloit, Wisconsin (I-39 and I-90 to Green Bay, Wisconsin (US-41)
Associated routes: none
I-44.svg I-44 Wichita Falls, Texas (US-287) to St. Louis, Missouri (I-55)
Associated routes: I-244, I-444*
I-45.svg I-45 Galveston, Texas (TX-87) to Dallas, Texas (I-30)
Associated route: I-345*
I-49.svg I-49 Lafayette, Louisiana (I-10) to Shreveport, Louisiana (I-20)
Associated routes: none
I-55.svg I-55 Laplace, Louisiana (I-10) to Chicago, Illinois (US-41, Lake Shore Drive)
Associated routes: I-155, I-255, I-355
I-57.svg I-57 Miner, Missouri (I-55) to Chicago, Illinois (I-94)
Associated routes: none
I-59.svg I-59 Slidell, Louisiana (I-10 & I-12) to Lookout Mountain, Georgia (I-24)
Associated routes: I-359, I-459, I-759
I-64.svg I-64 Weldon Spring, Missouri (I-70) to Chesapeake, Virginia (I-264 & I-664)
Associated routes: I-164, I-264, I-464, I-564, I-664
I-65.svg I-65 Mobile, Alabama (I-10) to Gary, Indiana (I-90)
Associated routes: I-165, I-465, I-565, I-865
I-66.svg I-66 Middletown, Virginia (I-81) to Washington, D.C. (US-29)
Associated routes: none
I-68.svg I-68 Morgantown, West Virginia (I-79) to Hancock, Maryland (I-70)
Associated routes: none
I-69.svg I-69 Indianapolis, Indiana (I-465) to Port Huron, Michigan (Canada)
Associated route: I-469
I-70.svg I-70 Cove Fort, Utah (I-15) to Baltimore, Maryland (I-695)
Associated routes: I-170, I-270, I-370, I-470, I-670
I-71.svg I-71 Louisville, Kentucky (I-64) to Cleveland, Ohio (I-90)
Associated routes: I-271, I-471
I-72.svg I-72 Hannibal, Missouri (US-61) to Champaign, Illinois (I-57)
Associated route: I-172
I-73.svg I-73 Candor, North Carolina (US-220) to Greensboro, North Carolina (I-40 & I-85)
Associated routes: none
I-74.svg I-74 West Bettendorf, Iowa (I-80) to Cincinnati, Ohio (I-75)
Associated route: I-474
I-74.svg I-74 East Cana, Virginia (I-77) to Mount Airy, North Carolina (US-52)
Associated routes: none
I-75.svg I-75 Hialeah, Florida (FL-826) to Sault Ste. Marie, Michigan (Canada)
Associated routes: I-175, I-275, I-375, I-475, I-575, I-675
I-76.svg I-76 West Denver, Colorado (I-70) to Big Springs, Nebraska (I-80)
Associated routes: none
I-76.svg I-76 East Westfield Center, Ohio (I-71) to Camden, New Jersey (I-295)
Associated routes: I-176, I-276, I-376, I-476, I-676
I-77.svg I-77 Columbia, South Carolina (I-26) to Cleveland, Ohio (I-90)
Associated routes: I-277
I-78.svg I-78 Union Twp., Pennsylvania (I-81) to New York, New York
Associated routes: I-278, I-478*, I-678, I-878*
I-79.svg I-79 Charleston, West Virginia (I-77) to Erie, Pennsylvania (PA-5)
Associated routes: I-279, I-579
I-80.svg I-80 San Francisco, California (U.S. Route 101) to Fort Lee, New Jersey (I-95)
Associated routes: I-180, I-280, I-380, I-480, I-580, I-680, I-780, I-880, I-980
I-81.svg I-81 Dandridge, Tennessee (I-40) to Fisher's Landing, New York (Canada)
Associated routes: I-181, I-381, I-481, I-581
I-82.svg I-82 Ellensburg, Washington (I-90) to Hermiston, Oregon (I-84)
Associated route: I-182
I-83.svg I-83 Baltimore, Maryland to Harrisburg, Pennsylvania (I-81)
Associated route: I-283
I-84.svg I-84 West Portland, Oregon (I-5) to Echo, Utah (I-80)
Associated route: I-184
I-84.svg I-84 East Scranton, Pennsylvania (I-81) to Sturbridge, Massachusetts (I-90)
Associated routes: I-384, I-684
I-85.svg I-85 Montgomery, Alabama (I-65) to Petersburg, Virginia (I-95)
Associated routes: I-185, I-285, I-385, I-485, I-585, I-985
I-86.svg I-86 West Heyburn, Idaho (I-84) to Pocatello, Idaho (I-15)
Associated routes: none
I-86.svg I-86 East Erie, Pennsylvania (I-90) to Elmira, New York (NY-17)
Associated routes: none
I-87.svg I-87 New York, New York (I-278) to Champlain, New York (Canada)
Associated routes: I-287, I-587, I-787
I-88.svg I-88 West Barstow, Illinois (I-80) to Chicago, Illinois (I-290)
Associated routes: none
I-88.svg I-88 East Binghamton, New York (I-81) to Schenectady, New York (I-90)
Associated routes: none
I-89.svg I-89 Concord, New Hampshire (I-93) to Highgate Springs, Vermont (Canada)
Associated route: I-189
I-90.svg I-90 Seattle, Washington (WA-519) to Boston, Massachusetts (MA-1A)
Associated routes: I-190, I-290, I-390, I-490, I-590, I-690, I-790, I-890, I-990
I-91.svg I-91 New Haven, Connecticut (I-95) to Derby Line, Vermont (Canada)
Associated routes: I-291, I-391, I-691
I-93.svg I-93 Canton, Massachusetts (I-95) to St. Johnsbury, Vermont (I-91)
Associated routes: I-293, I-393
I-94.svg I-94 Billings, Montana (I-90) to Port Huron, Michigan (Canada)
Associated routes: I-194, I-294, I-394, I-494, I-694, I-794, I-894
I-95.svg I-95 Miami, Florida (US-1) to Houlton, Maine (Canada)
Associated routes: I-195, I-295, I-395, I-495, I-595, I-695, I-795, I-895
I-96.svg I-96 Muskegon, Michigan (US-31) to Detroit, Michigan (I-75)
Associated routes: I-196, I-296*, I-496, I-696
I-97.svg I-97 Annapolis, Maryland (US-50) to Baltimore, Maryland (I-695)
Associated routes: none
I-99.svg I-99 Bedford, Pennsylvania (I-76) to Bellefonte, Pennsylvania (I-80)
Associated routes: none

Interstates outside of the mainland

Interstate Highways not only reside in the contiguous 48 states of the United States, but there are also Interstates in Hawaii, Alaska, and Puerto Rico.


Hawaiian Interstates

The Interstate Highways in the island of Oʻahu, Hawaii are signed with the standard Interstate shield, with the letter "H-" prefixed before the number. They are fully controlled-access routes built to the same standards as the mainland Interstate routes. H-4 and H-5 are proposed, but construction was often blocked by local activists, such as environmentalists seeking to preserve the rainforests, and Native Hawaiians oppose the routes being laid out on sacred tribal sites.

Interstate Route Length (miles)[1]
I-H1.svg Interstate H-1
Kapolei, Hawaii (HI-93) to Honolulu, Hawaii (HI-72)
Associated route: H-201
I-H2.svg Interstate H-2
Pearl City, Hawaii (H-1) to Wahiawa, Hawaii (HI-99)
I-H3.svg Interstate H-3
Halawa, Hawaii (H-1 & H-201) to Marine Corps Base 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.[2]


Map of the Interstates in Alaska

Alaska's "Interstates" are unsigned, though they all have state highway numbers (which do not match the Interstate numbers).[3]

Puerto Rico

Map of the Interstates in Puerto Rico

Like Alaska, Puerto Rico signs its "Interstates" as territorial routes, and the numbers do not match their official Interstate designations. PR-4 is proposed in the southeast side of the island. However, many of the territory's routes are freeway-standard toll roads.[4]

See also


  1. ^ a b Federal Highway Administration Route Log and Finder List - Table 1: Main Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways as of October 31, 2002
  2. ^ Federal Highway Administration. "FHWA Route Log and Finder List". Retrieved 2007-05-24.  ]
  3. ^ Voss, Oscar. "Alaska Roads - Interstate ends photos". Retrieved 2007-05-24.  
  4. ^ Voss, Oscar. "Puerto Rico road photos". Retrieved 2007-05-24.  

External links

Main Interstate Highways (major interstates highlighted)
4 5 8 10 12 15 16 17 19 20 22 24 25 26 27 29 30
35 37 39 40 43 44 45 49 55 57 59 64 65 66 68 69
70 71 72 73 74 75 76 (W) 76 (E) 77 78 79 80 81 82
83 84 (W) 84 (E) 85 86 (W) 86 (E) 87 88 (W) 88 (E) 89 90
91 93 94 95 96 97 99 (238) H-1 H-2 H-3
Unsigned  A-1 A-2 A-3 A-4 PRI-1 PRI-2 PRI-3
Lists  Primary  Main - Intrastate - Suffixed - Future - Gaps
Auxiliary  Main - Future - Unsigned
Other  Standards - Business - Bypassed


Got something to say? Make a comment.
Your name
Your email address