List of Interstate Highways

Last updated

Dwight D. Eisenhower National System of Interstate and Defense Highways
I-90.svg MUTCD M1-10.svg
Highway shield for Interstate 90 and the Eisenhower Interstate System
Map of current Interstates.svg
Interstate Highways in the 48 contiguous states
System information
FormedJune 29, 1956 [1]
Highway names
Interstates Interstate X (I-X)
System links

There are 70 primary Interstate Highways in the Interstate Highway System, a network of controlled-access freeways in the United States. They 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. Highways whose route numbers are divisible by "5" usually represent major coast-to-coast or border-to-border routes (ex. I-10 travels from Santa Monica, California, to Jacksonville, Florida, traveling from the Pacific to Atlantic oceans). Additionally, auxiliary highways have their numbering system where a different number prefixes the number of its parent highway.

Interstate Highway System United States highway system

The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, is a network of controlled-access highways that forms part of the National Highway System in the United States. Construction of the system was authorized by the Federal Aid Highway Act of 1956. The system extends throughout the contiguous United States and has routes in Hawaii, Alaska, and Puerto Rico.

Controlled-access highway Highway designed exclusively for high-speed vehicular traffic, with all traffic flow and ingress/egress regulated

A controlled-access highway is a type of highway which has been designed for high-speed vehicular traffic, with all traffic flow ingress- and egress-regulated. Common English terms are freeway, motorway and expressway. Other similar terms include Interstate and parkway. Some of these may be limited-access highways, although this term can also refer to a class of highway with somewhat less isolation from other traffic.

A routenumber is an identifying numeric designation assigned by a highway authority to a particular stretch of roadway to distinguish it from other routes and, in many cases, also to indicate its classification, general geographical location and/or orientation. The numbers chosen may be used solely for internal administrative purposes; however, in most cases they are also displayed on roadside signage and indicated on maps.


Five route numbers are duplicated in the system, though the corresponding highways are separated by state lines which prevent confusion. The main list that discusses the primary Interstate Highways in the contiguous United States is followed by sections regarding Alaska, Hawaii, and Puerto Rico.

Contiguous United States

There are 70 primary Interstate Highways listed in the table below.

NumberLength (mi) [2] Length (km)Southern or western terminusNorthern or eastern terminusFormedRemovedNotes
I-2.svg I2 46.875.3 US 83 in Penitas, Texas I-69E/US 77/US 83 in Harlingen, Texas 02013-01-012013currentTexas only
Associated routes: none
I-4.svg I4 132.3212.9 I-275 in Tampa, Florida I-95/SR 400 Daytona Beach, Florida 01959-01-011959currentFlorida only
Associated routes: none
I-5.svg I5 1,381.292,222.97 Fed. 1 at Mexican border in San Ysidro, California BC 99 at Canadian border in Blaine, Washington 01956-01-011956currentServes three states: CA, OR, WA
Associated routes: I-105, I-205, I-405, I-505, I-605, I-705, I-805; Future: I-305, I-905
I-8.svg I8 348.25560.45Sunset Cliffs Boulevard/Nimitz Boulevard in San Diego, California I-10 in Casa Grande, Arizona 01964-01-011964currentServes two states: CA, AZ
Associated routes: none
I-10.svg I10 2,460.343,959.53 SR 1 in Santa Monica, California I-95/US 17/SR 228 in Jacksonville, Florida 01957-01-011957currentServes eight states: CA, AZ, NM, TX, LA, MS, AL, FL
Associated routes: I-110, I-210, I-310, I-410, I-510, I-610, I-710, I-910
I-11.svg I11 22.84536.765 US 93 at Arizona state line I-215/I-515/US 93/US 95/SR 564 in Henderson, Nevada 02017-01-012017currentNevada only; planned extension north and south
Associated routes: none
I-12.svg I12 85.59137.74 I-10 in Baton Rouge, Louisiana I-10/I-59 in Slidell, Louisiana 01967-01-011967currentLouisiana only
Associated routes: none
I-14.svg I14 25.140.4 US 190/SH 9 in Copperas Cove, Texas I-35 in Belton, Texas 02017-01-262017currentTexas only; planned extension east and west
Associated routes: none
I-15.svg I15 1,433.522,307.03 I-8/SR 15 in San Diego, California Hwy. 4 at Canadian border in Sweetgrass, Montana 01957-01-011957currentServes six states: CA, NV, AZ, UT, ID, MT
Associated routes: I-115, I-215, I-315, I-515
I-16.svg I16 166.81268.45 I-75 in Macon, Georgia SR 404 and Montgomery Street/Martin Luther King Jr. Boulevard in Savannah, Georgia 01966-01-011966currentGeorgia only
Associated route: I-516
I-17.svg I17 145.76234.58 I-10 in Phoenix, Arizona I-40/SR 89A in Flagstaff, Arizona 01961-01-011961currentArizona only
Associated routes: none
I-19.svg I19 63.35101.95 Fed. 15 at Mexican border in Nogales, Arizona I-10 in Tucson, Arizona 01972-01-011972currentArizona only
Associated routes: none
Uses kilometers instead of miles
I-20.svg I20 1,539.382,477.39 I-10 between Kent and Toyah, Texas I-95 in Florence, South Carolina 01957-01-011957currentServes six states: TX, LA, MS, AL, GA, SC
Associated routes: I-220, I-520, I-820
I-22.svg I22 202.22325.44 I-269/US 78 near Byhalia, Mississippi I-65/US 31 in Birmingham, Alabama 02012-01-012012currentServes two states: Mississippi, Alabama
Planned associated routes: I-222, I-422
I-24.svg I24 316.36509.13 I-57 in Pulley's Mill, Illinois I-75 in Chattanooga, Tennessee 01962-01-011962currentServes four states: Illinois, Kentucky, Tennessee, Georgia
Associated route: I-124
I-25.svg I25 1,061.671,708.59 I-10/US 85/US 180 in Las Cruces, New Mexico I-90/US 87 in Buffalo, Wyoming 01957-01-011957currentServes three states: New Mexico, Colorado, Wyoming
Associated route: I-225
I-26.svg I26 304.64490.27 US 11W in Kingsport, Tennessee US 17 in Charleston, South Carolina 01960-01-011960currentServes three states: Tennessee, North Carolina, South Carolina
Associated routes: I-126, I-526
I-27.svg I27 124.13199.77 US 87/Loop 289 in Lubbock, Texas I-40/US 87/US 287 in Amarillo, Texas 01969-01-011969currentTexas only
Associated routes: none
I-29.svg I29 755.511,215.88 I-35/I-70 in Kansas City, Missouri US 81 and PTH 29 at Canadian border in Pembina, North Dakota 01958-01-011958currentServes four states: Missouri, Iowa, South Dakota, North Dakota
Associated routes: I-129, I-229
I-30.svg I30 366.76590.24 I-20 in Fort Worth, Texas I-40/US 65/US 67/US 167 in North Little Rock, Arkansas 01957-01-011957currentServes two states: Texas, Arkansas
Associated routes: I-430, I-530, I-630
I-35.svg I35 1,568.382,524.06 US 83/SH 359/BS I-35 and MX-85 at Mexican border in Laredo, Texas MN 61/LSCT/26th Avenue in Duluth, Minnesota 01956-01-011956currentServes six states: TX, OK, KS, MO, IA, MN
Associated routes: I-35E, I-35W, I-135, I-235, I-335, I-435, I-535, I-635
I-37.svg I37 143.00230.14 US 181 in Corpus Christi, Texas I-35/US 281 in San Antonio, Texas 01959-01-011959currentTexas only
Associated routes: none
I-39.svg I39 306.14492.68 I-55 in Normal, Illinois WIS 29/US 51 in Wausau, Wisconsin 01984-01-011984currentServes two states: Illinois, Wisconsin
Associated routes: none
I-40.svg I40 2,556.614,114.46 I-15 in Barstow, California US 117/NC 132 in Wilmington, North Carolina 01964-01-011964currentServes eight states: CA, AZ, NM, TX, OK, AR, TN, NC
Associated routes: I-140, I-240, I-440, I-540, I-640, I-840
I-41.svg I41 175282 I-94/US 41 in Russell, Illinois I-43 in Howard, Wisconsin 02015-01-012015currentServes two states:
Illinois, Wisconsin
Associated routes: none
I-43.svg I43 191.55308.27 I-39/I-90 in Beloit, Wisconsin I-41/US 41/US 141 in Howard, Wisconsin 01981-01-011981currentWisconsin only
Associated routes: none
I-44.svg I44 636.691,024.65 US 82/US 277/US 281/US 287 in Wichita Falls, Texas I-70 in St. Louis, Missouri 01958-01-011958currentServes three states: Texas, Oklahoma, Missouri
Associated routes: I-244, I-444
I-45.svg I45 284.91458.52 SH 87 in Galveston, Texas I-30/US 67/US 75 in Dallas, Texas 01971-01-011971currentTexas only
Associated route: I-345
I-49.svg I49 528.02849.77 I-10 in Lafayette, Louisiana I-435 in Kansas City, Missouri 01984-01-011984currentServes three states: Louisiana, Arkansas, Missouri
Associated routes: none
I-55.svg I55 964.251,551.81 I-10 in LaPlace, Louisiana US 41 in Chicago, Illinois 01960-01-011960currentServes six states: LA, MS, TN, AR, MO, IL
Associated routes: I-155, I-255, I-355; I-555
I-57.svg I57 386.12621.40 I-55 in Miner, Missouri I-94 in Chicago, Illinois 01965-01-011965currentServes two states: Missouri, Illinois. Planned in 1 more: Arkansas
Associated routes: none
I-59.svg I59 445.23716.53 I-10/I-12 in Slidell, Louisiana I-24 in Lookout Mountain, Georgia 01960-01-011960currentServes four states: Louisiana, Mississippi, Alabama, Georgia
Associated routes: I-359, I-459, I-759
I-64.svg I64 963.521,550.64 I-70 in Wentzville, Missouri I-264/I-664 in Chesapeake, Virginia 01961-01-011961currentServes six states: MO, IL, IN, KY, WV, VA
Associated routes: I-264, I-464, I-564, I-664
I-65.svg I65 887.301,427.97 I-10 in Mobile, Alabama I-90, US 12/US 20 in Gary, Indiana 01958-01-011958currentServes four states: Alabama, Tennessee, Kentucky, Indiana
Associated routes: I-165, I-265, I-465, I-565, I-865
I-66.svg I66 76.28122.76 I-81 in Front Royal, Virginia US 29 in Washington, D.C. 01961-01-011961currentServes District of Columbia and one state: Virginia
Associated routes: None, had one proposed auxiliary route, I-266, but was cancelled due to freeway revolts.
I-68.svg I68 113.15182.10 I-79 in Morgantown, West Virginia I-70 in Hancock, Maryland 01991-01-011991currentServes two states: West Virginia, Maryland
Associated routes: None
I-69.svg I69 700.781,127.80 I-69E/US 77 & I-69W/US 59 in Victoria, Texas (future) Hwy 402 at Canadian border in Port Huron, Michigan 01957-01-011957currentUnfinished Texas section: Rosenberg (US-59/Spur 529) to Splendora (US 59/Mandell Road)
Unfinished Mississippi-Tennessee section: Banks, Mississippi (MS 304/MS 713) to Frayser, Tennessee (US 51/TN 3)
Unfinished Indiana section: Martinsville, Indiana to Indianapolis, Indiana
Serves six states: TX, MS, TN, KY, IN, MI. Planned/started in 2 more: LA, AR
Associated routes: I-69C, I-69E, I-69W, I-169, I-269, I-369, I-469; Planned: I-169 in Tennessee, I-369 in Kentucky
I-70.svg I70 2,150.573,461.01 I-15 in Cove Fort, Utah Park and ride in Baltimore, Maryland 01956-01-011956currentServes 10 states: UT, CO, KS, MO, IL, IN, OH, WV, PA, MD
Associated routes: I-170, I-270, I-370, I-470, I-670
I-71.svg I71 345.57556.14 I-64 in Louisville, Kentucky I-90 in Cleveland, Ohio 01959-01-011959currentServes two states: Kentucky, Ohio
Associated routes: I-271, I-471
I-72.svg I72 179.29288.54 US 61 in Hannibal, Missouri I-57 in Champaign, Illinois 01970-01-011970currentServes two states: Missouri, Illinois
Associated route: I-172
I-73.svg I73 80.85130.12 US 220 near Ellerbe, North Carolina I‑840/Bryan Boulevard in Greensboro, North Carolina 01997-01-011997currentNorth Carolina only
Associated routes: none
I-74.svg I74 488.83786.70 I-80 in Bettendorf, Iowa NC 41 near Lumberton, North Carolina 01974-01-011974currentServes five states: IA, IL, IN, OH, NC
Associated routes: I-474
I-75.svg I75 1,786.472,875.04 SR 826 near Hialeah, Florida Sault Ste. Marie, Michigan (Canada)01958-01-011958currentServes six states: FL, GA, TN, KY, OH, MI
Associated routes: I-175, I-275, I-375, I-475, I-575, I-675
I-76.svg I76 186.48300.11 Denver, Colorado (I-70) Big Springs, Nebraska (I-80)01975-01-011975currentServes two states: Colorado, Nebraska
Associated routes: none
I-76.svg I76 435.66701.13 Westfield Center, Ohio (I-71) Bellmawr, New Jersey (I-295)01964-01-011964currentServes three states: Ohio, Pennsylvania, New Jersey
Associated routes: I-176, I-276, I-376, I-476, I-676; Future: I-576
I-77.svg I77 610.10981.86 Columbia, South Carolina (I-26) Cleveland, Ohio (I-90)01958-01-011958currentServes five states: South Carolina, North Carolina, Virginia, West Virginia, Ohio
Associated route: I-277
I-78.svg I78 146.28235.41 Union Township, Pennsylvania (I-81) New York City 01957-01-011957currentServes three states: Pennsylvania, New Jersey, New York
Associated routes: I-278, I-478, I-678, I-878
I-79.svg I79 343.46552.75 Charleston, West Virginia (I-77) Erie, Pennsylvania (PA-5)01967-01-011967currentServes two states: West Virginia, Pennsylvania
Associated routes: I-279, I-579
I-80.svg I80 2,899.594,666.44 San Francisco, California (US 101) Teaneck, New Jersey (I-95)01956-01-011956currentServes 11 states: CA, NV, UT, WY, NE, IA, IL, IN, OH, PA, NJ
Associated routes: I-180, I-238, I-280, I-380, I-480, I-580, I-680, I-780, I-880, I-980
I-81.svg I81 855.021,376.02 Dandridge, Tennessee (I-40) Fisher's Landing, New York (Canada)01961-01-011961currentServes six states: TN, VA, WV, MD, PA, NY
Associated routes: I-381, I-481, I-581, I-781
I-82.svg I82 143.58231.07 Ellensburg, Washington (I-90) Hermiston, Oregon (I-84)01957-01-011957currentServes two states: Washington, Oregon
Associated route: I-182
I-83.svg I83 85.03136.84 Baltimore, Maryland Harrisburg, Pennsylvania (I-81)01959-01-011959currentServes two states: Maryland, Pennsylvania
Associated route: I-283
I-84.svg I84 769.621,238.58 Portland, Oregon (I-5) Echo, Utah (I-80)01980-01-011980currentServes three states: Oregon, Idaho, Utah
Associated route: I-184
I-84.svg I84 232.71374.51 Scranton, Pennsylvania (I-81) Sturbridge, Massachusetts (I-90)01963-01-011963currentServes four states: Pennsylvania, New York, Connecticut, Massachusetts
Associated routes: I-384, I-684
I-85.svg I85 666.051,071.90 Montgomery, Alabama (I-65) Petersburg, Virginia (I-95)01958-01-011958currentServes five states: Alabama, Georgia, South Carolina, North Carolina, Virginia
Associated routes: I-185, I-285, I-385, I-485, I-585, I-785, I-985; Planned: I-685
I-86.svg I86 62.85101.15 Heyburn, Idaho (I-84) Pocatello, Idaho (I-15)01980-01-011980currentIdaho only
Associated routes: none
I-86.svg I86 223.39359.51 Erie, Pennsylvania (I-90) Windsor, New York (NY 79)01999-01-011999currentServes two states: Pennsylvania, New York
Associated routes: none
I-87.svg I87 12.920.8 Raleigh, North Carolina (I-440/US 64/US 264) Wendell, North Carolina (US 64/US 264)02017-01-012017currentNorth Carolina only
Associated routes: None, will eventually have one spur route, I-587.
I-87.svg I87 333.49536.70 New York City (I-278) Champlain, New York (A-15 at Canadian border)01957-01-011957currentNew York only
Associated routes: I-287, I-587, I-787
I-88.svg I88 140.6226.3 Barstow, Illinois (I-80) Hillside, Illinois (I-290)01987-01-011987currentIllinois only
Associated routes: none
I-88.svg I88 117.75189.50 Binghamton, New York (I-81) Schenectady, New York (I-90)01968-01-011968currentNew York only
Associated routes: none
I-89.svg I89 191.12307.58 Bow, New Hampshire (I-93) Highgate Springs, Vermont (Route 133 at Canadian border/future A-35)01960-01-011960currentServes two states: New Hampshire, Vermont
Associated route: I-189
I-90.svg I90 3,020.444,860.93 Seattle, Washington (WA 519) Boston, Massachusetts (MA 1A)01956-01-011956currentServes 13 states: WA, ID, MT, WY, SD, MN, WI, IL, IN, OH, PA, NY, MA
Associated routes: I-190, I-290, I-390, I-490, I-590, I-690, I-790, I-890, I-990
I-91.svg I91 290.37467.31 New Haven, Connecticut/North Haven, Connecticut (I-95) Derby Line, Vermont (A-55 at Canadian border)01958-01-011958currentServes three states: Connecticut, Massachusetts, Vermont
Associated routes: I-291, I-391, I-691
I-93.svg I93 189.95305.69 Canton, Massachusetts (I-95) St. Johnsbury, Vermont (I-91)01957-01-011957currentServes three states: Massachusetts, New Hampshire, Vermont
Associated routes: I-293, I-393
I-94.svg I94 1,585.202,551.13 I-90 in Billings, Montana Highway 402 at Canadian border in Port Huron, Michigan 01956-01-011956currentServes seven states: MT, ND, MN, WI, IL, IN, MI
Associated routes: I-194, I-294, I-394, I-494, I-694, I-794, I-894
I-95.svg I95 1,908.483,071.40 US 1 in Miami, Florida NB 95 at Canadian border in Houlton, Maine 01957-01-011957currentServes DC and 15 states: FL, GA, SC, NC, VA, MD, DE, PA, NJ, NY, CT, RI, MA, NH, ME
Associated routes: I-195, I-295, I-395, I-495, I-595, I-695, I-795, I-895
I-96.svg I96 192.06309.09 Muskegon, Michigan (US 31) Detroit, Michigan (I-75)01959-01-011959currentMichigan only
Associated routes: I-196, I-296, I-496, I-696
I-97.svg I97 17.6228.36 Annapolis, Maryland (US 50) Baltimore, Maryland (I-695/I-895)01987-01-011987currentMaryland only
Associated routes: None, had 2 auxiliary routes planned, I-197 and I-297, but they were replaced by I-595 and MD Route 3.
I-99.svg I99 98.34158.26 Bedford, Pennsylvania (I-70/I-76) Painted Post, New York (I-86)01998-01-011998currentUnfinished Pennsylvania section: Bellefonte, Pennsylvania (I-80) to New York border near Lawrenceville, Pennsylvania (US 15)
Serves two states: Pennsylvania, New York
Associated routes: none

Other jurisdictions

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:

Federal Highway Administration government agency

The Federal Highway Administration (FHWA) is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two programs, the Federal-aid Highway Program and the Federal Lands Highway Program. Its role had previously been performed by the Office of Road Inquiry, Office of Public Roads and the Bureau of Public Roads.

Alaska State of the United States of America

Alaska is a U.S. state in the northwest extremity of the United States West Coast, just across the Bering Strait from Asia. The Canadian province of British Columbia and territory of Yukon border the state to the east and southeast. Its most extreme western part is Attu Island, and it has a maritime border with Russia to the west across the Bering Strait. To the north are the Chukchi and Beaufort seas—southern parts of the Arctic Ocean. The Pacific Ocean lies to the south and southwest. It is the largest U.S. state by area and the seventh largest subnational division in the world. In addition, it is the 3rd least populous and the most sparsely populated of the 50 United States; nevertheless, it is by far the most populous territory located mostly north of the 60th parallel in North America: its population—estimated at 738,432 by the United States Census Bureau in 2015— is more than quadruple the combined populations of Northern Canada and Greenland. Approximately half of Alaska's residents live within the Anchorage metropolitan area. Alaska's economy is dominated by the fishing, natural gas, and oil industries, resources which it has in abundance. Military bases and tourism are also a significant part of the economy.

Puerto Rico Unincorporated territory of the United States

Puerto Rico, officially the Commonwealth of Puerto Rico and briefly called Porto Rico, is an unincorporated territory of the United States located in the northeast Caribbean Sea, approximately 1,000 miles (1,600 km) southeast of Miami, Florida.


The Interstate Highways in 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.

Oahu The third-largest of the Hawaiian Islands and site of the state capital Honolulu

Oʻahu, known as "The Gathering Place", is the third-largest of the Hawaiian Islands. It is home to roughly one million people—about two-thirds of the population of the U.S. state of Hawaii. The state capital, Honolulu, is on Oʻahu's southeast coast. Including small associated islands such as Ford Island and the islands in Kāneʻohe Bay and off the eastern (windward) coast, its area is 596.7 square miles (1,545.4 km2), making it the 20th-largest island in the United States.

Hawaii State of the United States of America

Hawaii is the 50th and most recent state to have joined the United States, having received statehood on August 21, 1959. Hawaii is the only U.S. state located in Oceania, the only U.S. state located outside North America, and the only one composed entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean.

NumberLength (mi) [2] Length (km)Southern or western terminusNorthern or eastern terminusFormedRemovedNotes
I-H1.svg H-1 27.1643.71 Route 93 in Kapolei Route 72 in Honolulu 01959-01-011959currentAssociated route: H-201
I-H2.svg H-2 8.3313.41 H-1 in Pearl City Route 99 in Wahiawa 01976-01-011976current
I-H3.svg H-3 15.3224.66 H-1 & H-201 in Halawa Marine Corps Base Hawaii 01997-01-011997current
H-4 6.510.5Was to have provided relief around the congested areas of H-1, but the idea was not popular and was never built.
  •       Former


Map of the Interstates in Alaska Interstate Alaska map.png
Map of the Interstates in Alaska

Alaska's Interstate Highways are unsigned as such, although they all have state highway numbers that do not match the Interstate Highway numbers. [4]

NumberLength (mi) [2] Length (km)Southern or western terminusNorthern or eastern terminusFormedRemovedNotes
I-A1.svg A1 408.23656.98 Anchorage Canadian border in Alcan Border 01976-01-011976current Glenn Highway, Richardson Highway, Tok Cut-Off, Alaska Highway [5] [6] [7] [8]
I-A2.svg A2 202.18325.38 Tok Fairbanks 01976-01-011976current Alaska Highway, Richardson Highway [6] [7] [8]
I-A3.svg A3 148.12238.38 Anchorage Soldotna 01976-01-011976current Seward Highway, Sterling Highway [5] [7] [8]
I-A4.svg A4 323.69520.93 Gateway, near Palmer Fairbanks 01976-01-011976current Parks Highway [5] [6] [7] [8]

Puerto Rico

Map of the Interstates in Puerto Rico Puerto Rico Interstates.svg
Map of the Interstates in Puerto Rico

Like Alaska, Puerto Rico signs its Interstate Highways as territorial routes, and the numbers do not match their official Interstate Highway designations. Many of the territory's routes are freeway-standard toll roads. [9]

Toll road roadway for which a fee (or toll) is assessed for passage

A toll road, also known as a turnpike or tollway, is a public or private road for which a fee is assessed for passage. It is a form of road pricing typically implemented to help recoup the cost of road construction and maintenance.

NumberLength (mi) [2] Length (km)Southern or western terminusNorthern or eastern terminusFormedRemovedNotes
I-PR1.svg PRI-1 71.08114.39 PR-2 in Ponce PR-2 in San Juan 01953-01-011953currentFollows PR-52
I-PR2.svg PRI-2 138.13222.30 PR-1 in Ponce PR-3 in San Juan 01953-01-011953currentFollows PR-22
I-PR3.svg PRI-3 65.27105.04 PR-3 in Humacao PR-2 in San Juan 01953-01-011953currentFollows PR-66

The title of interactive fiction I-0 refers to the fictional "Interstate Zero". [10]

I-0 is a piece of anonymous interactive fiction about the adventures of a teenage girl hitch-hiking on an Interstate Highway. It won the Best Game and Best Individual Player Character awards at the 1997 Xyzzy Awards, and was a finalist for six other categories. The game was generally praised for its branching plot structure and multiple puzzle solutions. The game is available freely online.

See also

Related Research Articles

Interstate H-1 is the busiest Interstate Highway in the US state of Hawaii. The highway is located on the island of O‘ahu. Despite the number, this is an east–west highway; the 'H'-series numbering reflects the order in which routes were funded and built. H-1 goes from Route 93 in Kapolei to Route 72 in Kāhala. East of Middle Street in Honolulu, H-1 is also known as the Lunalilo Freeway and is sometimes signed as such at older signs in central Honolulu. West of Middle Street, H-1 is also known as the Queen Liliʻuokalani Freeway; this name is shown on some roadmaps. It is both the southernmost and westernmost signed Interstate Highway in the United States.

Interstate 296 (I-296) is a part of the Interstate Highway System in the US state of Michigan. It is a state trunkline highway that runs for 3.43 miles (5.52 km) entirely within the Grand Rapids area. Its termini are I-196 near downtown Grand Rapids and I-96 on the north side of Grand Rapids in Walker. For most of its length, the Interstate runs concurrently with U.S. Highway 131 (US 131), which continues as a freeway built to Interstate Highway standards north and south of the shorter I-296. The highway was first proposed in the late 1950s and opened in December 1962, but the Michigan Department of Transportation (MDOT) has since eliminated all signage for I-296 and removed the designation from their official state map. The designation is therefore unsigned, but still listed on the Interstate Highway System route log maintained by the Federal Highway Administration (FHWA).

Interstate H-201 (H-201) is the only auxiliary Interstate Highway located in the U.S. state of Hawaii, serving the island of O‘ahu. The H-201 designation is also known as the Moanalua Freeway. The 4.1-mile-long (6.6 km) loop route connects exits 13 and 19 on H-1, passing Fort Shafter, Tripler Army Medical Center, and Red Hill.

Interstate Highways in Alaska Interstate Highways in Alaska

The Interstate Highways in Alaska are all owned and maintained by the U.S. state of Alaska. The Alaska Department of Transportation & Public Facilities (DOT&PF) is responsible for the maintenance and operations of the Interstate Highways. The Interstate Highway System in Alaska comprises four highways that cover 1,082.22 miles (1,741.66 km). The longest of these is A-1, at 408.23 miles (656.98 km) long, while the shortest route is A-3, at 148.12 miles (238.38 km) long. All Interstates in Alaska are unsigned and are not generally referred to by their highway numbers.

Interstate 115 (I-115) is a 1.194-mile-long (1.922 km) auxiliary Interstate Highway which connects I-15/I-90 to Butte in the U.S. state of Montana. The highway is concurrent with I-15 Bus./I-90 Bus. for its entire length. The highway travels from an incomplete interchange with I-15/I-90 through generally rural areas in western Butte. It also has an interchange with Excelsior Avenue before terminating. The entire route was improved to interstate standards during the 1960s, and was improved in 2005.

Interstate 164 (I-164) was a spur highway of I-64, between that highway and U.S. Highway 41 (US 41) in Evansville, Indiana. I-164, also known as the Robert D. Orr Highway, had a total length of 21.24 miles (34.18 km). Requested as an Interstate and approved in 1968, the freeway was opened to traffic on August 2, 1990.

An unsigned highway is a highway that has been assigned a route number, but does not bear road markings that would conventionally be used to identify the route with that number. Highways are left unsigned for a variety of reasons, and examples are found throughout the world. Depending on the policy of the agency that maintains the highway, and the reason for not signing the route, the route may instead be signed a different designation from its actual number, with small inventory markers for internal use, or with nothing at all.


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