kids encyclopedia robot

List of auxiliary Interstate Highways facts for kids

Kids Encyclopedia Facts
Interstate 295 marker
Highway shield for Interstate 295
Interstate Highways in the 48 contiguous states
Quick facts for kids
System information
Formed: June 29, 1956
Highway names
Interstates: Interstate X (I-X)
System links

Auxiliary Interstate Highways (also called three-digit Interstate Highways) are a subset of highways within the United States' Interstate Highway System. The 323 auxiliary routes generally fall into three types: spur routes, which connect to or intersect the parent route at one end; bypasses, which connect to the parent route at both ends; and beltways, which form a circle that intersects the parent route at two locations. Some routes connect to the parent route at one end but to another route at the other end; some states treat these as spurs while others treat them as bypasses. Like the primary Interstate Highways, auxiliary highways meet Interstate Highway standards (with rare exceptions).

The shorter auxiliary routes branch from primary routes; their numbers are based on the parent route's number. All of the supplement routes for Interstate 95 (I-95) are designated with a three-digit number ending in "95": I-x95. With some exceptions, spur routes are numbered with an odd hundreds digit (such as I-395), while bypasses and beltways are numbered with an even hundreds digit (such as I-695). Because longer Interstates may have many such supplemental routes, the numbers can repeat from state to state along their route, but they will not repeat within a state.

There are three states that have no auxiliary Interstate Highways: Alaska, Arizona, and New Mexico. North Dakota has an auxiliary route, but it is unsigned, and Wyoming's does not meet Interstate Highway standards.

Terminology and guidelines

FHWA Auxiliary Route Numbering Diagram
Routes that begin with an even number generally connect to the main highway in two locations, while odd numbers only connect in one location.

Auxiliary Interstates are divided into three types: spur, loop, and bypass routes.

The first digit of the three digits usually signifies whether a route is a bypass, spur, or beltway. The last two digits are derived from the main Interstate Highway. For instance, I-515 contains an odd number in the first digit (5), which indicates that this freeway is a spur. The last two digits signify the highway's origin. In this case, the "15" in I-515 shows that it is a supplement to I-15.

Exceptions to the standard numbering guidelines exist for a number of reasons. In some cases, original routes were changed, extended, or abandoned, leaving discrepancies in the system. In other cases, it may not be possible to use the proper number because the limited set of available numbers has been exhausted, causing a "non-standard" number to be used.

Spur route

A spur route's number usually has an odd number for its first digit. It is usually one of the following:

  • It may serve another section of a city or metropolitan area not served by the main freeway (most often the central business district), terminating at a regular city street/avenue or at a substandard freeway, such as I-185 in Columbus, Georgia.
  • It may represent the first portion of a contemplated extended freeway, one that downgrades to below Interstate standards with plans to upgrade it later on. An example is I-540 in Arkansas.
  • It may connect two unrelated Interstate highways—as I-390 in New York State and I-355 in Illinois do.
    • States differ on their interpretation of the numbering convention in this case. In the I-390 example above, the route has both ends at Interstates, but not at the same Interstate on both ends, and is assigned an odd first digit. Another example is I-275 in Tennessee: it is a connector between I-40 and I-75 (a similar case of having both ends at Interstates but not at the same Interstate) and is assigned an even first digit.
    • This may even vary within the same state. For example, in Michigan, both I-196 and I-696 intersect I-96 at one end and I-94 at the other end.

Examples include:

Sometimes, a three-digit Interstate Highway branches off from another three-digit Interstate Highway. These spurs do not connect directly with their parent highways, but are associated with them via the three-digit highways they do intersect with.

Examples include:

Bypass

A bypass route may traverse around a city, or may run through it with the mainline bypassing. In a typical 3-digit Interstate Highway, bypasses usually have both its two termini junctioned with another Interstate highway. Bypass routes are preceded by an even number in the first digit.

Examples include:

In the case of an auxiliary Interstate highway which has both ends at Interstates but not the same Interstate, some states treat these as bypasses while others treat these as spurs—see Spur route above.

Beltway

A beltway (also known as a loop route) completely surrounds a metropolitan city, and it is often connected with multiple junctions to other routes. Unlike other auxiliary Interstate Highways (and by extension, all primary Interstate Highways), beltways do not have termini; however, they have a place where the highway mileage resets to zero. Beltways are also preceded by an even number in the first digit.

Some examples of beltways include:

Auxiliary Interstates

Note: this table sorts the route numbers by parent highway.
Number Length (mi) Length (km) Southern or western terminus Northern or eastern terminus Formed Removed Notes
H-201 4.10 6.60 H-1 in Halawa, HI H-1 in Honolulu, HI 2004 current Signed as Route 78 until 2004
I-105 17.32 27.87 SR 1 in El Segundo, CA I-605 in Norwalk, CA 1963 current Replaced segments of SR 42
I-205 12.97 20.87 I-580 near Tracy, CA I-5 near Tracy, CA 1970 current
I-305 6.00 9.66 I-80 in West Sacramento, CA I-80 Bus/US 50/SR 99 in Sacramento, CA 1981 current Unsigned
I-405 72.15 116.11 I-5 in Irvine, CA I-5 in Mission Hills, CA 1964 current
I-505 32.98 53.08 I-80 in Vacaville, CA I-5 in Dunnigan, CA 1977 current Originally part of I-5W
I-605 27.40 44.10 I-405 in Seal Beach, CA I-210 in Irwindale, CA 1964 current
I-805 28.02 45.09 I-5 in San Ysidro, CA I-5 in Sorrento Valley, CA 1959 current
I-905 8.96 14.42 I-5 in San Ysidro, CA Fed. 2 at the United States-Mexico border in Otay Mesa, CA proposed — Currently SR 905, proposed to be signed as an Interstate
I-105 3.49 5.62 OR 99 in Eugene, OR I-5 in Springfield, OR 1958 current
I-305 — — Pine Street in Salem, OR I-5 in Keizer, OR 1957 1976 Canceled
I-405 3.53 5.68 I-5 in Portland, OR I-5 in Portland, OR 1958 current
I-505 3.17 5.10 US 30 in Portland, OR I-405 in Portland, OR 1969 1979 Canceled
I-205 36.64 58.97 I-5 in Tualatin, OR I-5 in Salmon Creek, WA 1958 current
I-405 30.30 48.76 I-5/SR 518 in Tukwila, WA I-5/SR 525 in Lynnwood, WA 1957 current
I-605 — — WA 99 in Federal Way, WA I-5 in Everett, WA — — Never built, was planned to bypass Seattle, WA
I-705 1.50 2.41 I-5/SR 7 in Tacoma, WA Schuster Parkway in Tacoma 1978 current
I-210 4.9 7.9 I-10 in Mobile, AL I-65 in Prichard, AL — — Currently I-165, the route number was decommissioned because it had no connection to I-10
I-410 — — I-10/I-17 in Phoenix, AZ I-10 in Phoenix, AZ — — Now part of I-10 in Phoenix, AZ
I-510 — — I-10/SR 51 in Phoenix, AZ SR 101 in Phoenix, AZ — — Currently designated as SR 51 (Piestewa Freeway)
I-710 — — I-10 in Tucson, AZ North Campbell Avenue/East 6th Street in Tucson, AZ — — Mostly never built freeway that was to connect to University of Arizona campus from I-10
I-110 20.43 32.88 SR 47 in San Pedro, CA I-10/SR 110 in Los Angeles, CA 1978 current Originally part of US 6, then signed as SR 11
I-210 48.72 78.41 I-5 in Sylmar, CA SR 57/SR 210 in Glendora, CA 1964 current Does not connect physically with I-10 as segment from SR 57 east to I-10 is still signed as SR 210, formerly SR 30 prior to 2007.
I-710 19.66 31.64 Terminal Island in Long Beach, CA Valley Boulevard in Alhambra, CA 1983 current Originally signed as SR 7
I-110 6.94 11.17 US 98 Bus. near Pensacola, FL I-10 near Pensacola, FL 1969 current
I-110 8.89 14.31 I-10 in Baton Rouge, LA US 61 in Baton Rouge, LA 1964 current
I-210 12.40 19.96 I-10 west of Lake Charles, LA I-10 east of Lake Charles, LA 1964 current
I-310 11.25 18.11 US 90/LA 3127 in Boutte, LA I-10 west of Kenner, LA 1983 current
I-310 2.70 4.35 US 90 Bus. in New Orleans, LA I-10 in New Orleans, LA 1964 1969 Canceled Vieux Carré Riverfront Expressway
I-410 1.90 3.06 LA 67 in Baton Rouge, LA I-10 in Baton Rouge, LA 1961 1964 Renumbered as I-110
I-410 48.5 78.1 I-10 west of New Orleans, LA I-10 in New Orleans, LA 1969 1977 Canceled southern bypass of New Orleans; completed portions became I-310 and I-510
I-510 3.04 4.89 LA 47 in New Orleans, LA I-10/LA 47 in New Orleans, LA 1992 current
I-610 4.52 7.27 I-10 at Metairie–New Orleans, LA line I-10 in New Orleans, LA 1965 current
I-910 9.70 15.61 US 90 Bus. in Marrero, LA I-10/US 90 Bus. in New Orleans, LA 1999 current Unsigned; completely concurrent with US 90 Bus.; both designation are temporary placeholders for Future I-49
I-110 4.10 6.60 US 90 in Biloxi, MS I-10 in D'Iberville, MS 1988 current
I-310 — — US 90 near the Port of Gulfport, MS I-10 in Gulfport, MS proposed — Future spur into Gulfport, MS
I-110 0.92 1.48 Av Abraham Lincoln at the United States-Mexico border in El Paso, TX I-10 in El Paso, TX 1967 current
I-410 49.49 79.65 Beltway around San Antonio, TX 1959 current
I-610 37.97 61.11 Beltway around Houston, TX 1975 current
I-215 54.50 87.71 I-15 in Murrieta, CA I-15 in Devore, CA 1982 current Originally signed as I-15E, then SR 215
I-115 1.19 1.92 I-15/I-90 in Butte, MT Iron Street in Butte, MT 1971 current
I-315 0.83 1.34 I-15 in Great Falls, MT I-15 Bus/US 89 in Great Falls, MT 1960 current Unsigned
I‑215 11.10 17.86 I-15/Clark County Route 215 in Enterprise, NV I-515/US 93/SR 564 in Henderson, NV 1996 current
I‑515 20.54 33.06 I-215/I-11/US 93/US 95 in Henderson, NV I-15/US 93/US 95 in Las Vegas, NV 1976 current Not signed until 1994, this route is entirely concurrent with US 93/US 95; will be decommisioned and replaced by a northward extension of I-11 in 2024
I-215 29.02 46.70 I-80 in Salt Lake City, UT I-15 in North Salt Lake, UT 1963 current
I-415 2.39 3.85 I-80 in Salt Lake City, UT 4430 S in Holladay, UT 1965 1969 Designation was scrapped to provide a single route number 215 for the entire route.
I-516 6.49 10.44 SR 21/SR 204 in Savannah, GA SR 21 in Garden City, GA 1985 current
I-420 5.40 8.69 I-285 in College Park, GA I-20 in Atlanta, GA 1983 1986 Never built, was planned to bypass Atlanta, GA
I-520 23.34 37.56 I-20 in Augusta, GA I-20 in North Augusta, SC 1980 current
I-220 17.62 28.36 I-20/LA 3132 in Shreveport, LA I-20 in Bossier City, LA 1979 current
I-420 10.20 16.42 I-20 in West Monroe, LA I-20 in Monroe, LA 1957 1964 Canceled bypass of Monroe
I-220 12.01 19.33 I-20 in Jackson, MS I-55 in Ridgeland, MS 1981 current
I-820 35.17 56.60 I-20 in Fort Worth, TX I-20/US 287 in Fort Worth, TX 1959 current
I-222 — — I-22 in Graysville, AL I-422 in Brookside, AL proposed — Proposed connector between I-422 and I-22 due to the inability to make a direct connection between the two routes.
I-422 — — I-20/I-59/I-459/US 11 in Bessemer, AL I-59 in Argo, AL proposed — Currently under construction; will only be indirectly connected to I-22 via I-222.
I-124 1.97 3.17 I-24 in Chattanooga, TN US 27 in Chattanooga, TN 1960 current Unsigned
I-225 12.00 19.31 I-25 in Denver, CO I-70 in Aurora, CO 1976 current
I-425 5.31 8.55 I-25/US 36 at Welby, CO I-70/US 36 at Denver, CO — 1959 Renumbered as I-270 by AASHTO
I-126 3.68 5.92 I-26 in Columbia, SC US 21/US 76/US 176/US 321 in Columbia, SC 1961 current
I-326 5.24 8.43 I-26 in Cayce, SC SC 48 in Columbia, SC 1976 1995 Now part of I-77, formerly unsigned
I-526 19.26 31.00 US 17 in Charleston, SC I-526 Bus./US 17 in Mount Pleasant, SC 1989 current
I-129 3.48 5.60 US 20/US 75/US 77 in South Sioux City, NE I-29/US 20/US 75 in Sioux City, IA 1976 current
I-229 14.97 24.09 I-29 in St. Joseph, MO I-29/US 59/US 71 in St. Joseph, MO 1986 current
I-229 11.33 18.23 I-29 in Sioux Falls, SD I-90 near Sioux Falls, SD 1966 current
I-130 5 8 I-30/I-49 in Texarkana, AR US 59/US 71 near Texarkana, AR 2000 2014 Was given a future designation during its existence due to not being upgraded to Interstate Highway standards; freeway became part of I-49 once completed
I-430 12.93 20.81 I-30/US 67 in Little Rock, AR I-40/US 65 in Little Rock, AR 1980 current
I-530 46.65 75.08 US 65 in Pine Bluff, AR I-30/I-440 in Little Rock, AR 1999 current
I-630 7.40 11.91 I-430 near Little Rock, AR I-30 in Little Rock, AR 1985 current
I-235 13.78 22.18 I-35/I-80 in West Des Moines, IA I-35/I-80 near Des Moines, IA 1961 current
I-135 95.74 154.08 Kansas Turnpike/I-35 in Wichita, KS I-70/US 81 in Salina, KS 1976 current
I-235 16.52 26.59 I-135/US 81 in Wichita, KS I-135/US 81/K-15/K-254 in Wichita, KS 1965 current
I-335 50.13 80.68 I-35/Kansas Turnpike/US 50 in Emporia, KS I-470/Kansas Turnpike in Topeka, KS 1987 current
I-435 80.81 130.05 Beltway around Kansas City, KS, and Kansas City, MO 1965 current
I-635 8.90 14.32 I-35 in Overland Park, KS I-29/US 71 in Kansas City, MO 1968 current
I-335 2.74 4.41 I-94 in Minneapolis, MN I-35W in Minneapolis, MN 1964 1978 Canceled
I-535 2.78 4.47 I-35/US 53 in Duluth, MN US 53/WIS 35 in Superior, WI 1971 current
I-235 5.36 8.63 I-35/I-40 in Oklahoma City, OK I-44 in Oklahoma City, OK 1989 current
I-335 19.6 31.5 SE 89th Street in Oklahoma City, OK I-44 in Luther, OK 2024 current Routed along the Kickapoo Turnpike
I-635 37.00 59.55 SH 121 in Grapevine, TX I-20 in Balch Springs, TX 1959 current
I-440 9.96 16.03 I-30/I-530 near Little Rock, AR I-40/AR 440 near Little Rock, AR 2003 current
I-540 15.87 25.54 US 271/AR 253 near Fort Smith, AR I-40 in Van Buren, AR 1965 current
I-140 6.79 10.93 US 17 near Winnabow, NC I-40/US 17 in Wilmington, NC 2008 current
I-240 9.54 15.35 I-26/I-40/US 74 near Asheville, NC I-40/US 74A in Asheville, NC 1980 current
I-440 16.77 26.99 I-40/US 1/US 64 near Cary, NC I-40 near Raleigh, NC 1991 current
I-540 25.84 41.59 I-40 near Durham, NC I-87/US 64/US 264 near Knightdale, NC 1997 current
I-840 21.9 35.2 I-40/I-73/US 421 in Greensboro, NC I-40/I-85/I-785/I-85 Bus. in Greensboro, NC 2011 current
I-240 16.22 26.10 I-44/US 62 in Oklahoma City, OK I-40/US 270 in Oklahoma City, OK 1965 current
I-440 9.96 16.03 I-40/I-240 near Oklahoma City, OK I-35 in Oklahoma City, OK — 1975 Now part of I-44
I-140 11.17 17.98 I-40 near Farragut, TN US 129 near Alcoa, TN 1987 current
I-240 19.27 31.01 I-40 in Memphis, TN I-40 in Memphis, TN 1970 current
I-440 7.64 12.30 I-40 in Nashville, TN I-24 in Nashville, TN 1987 current
I-640 7.03 11.31 I-40 in Knoxville, TN I-40 in Knoxville, TN 1982 current
I-840 77.28 124.37 I-40 near Dickson, TN I-40 near Lebanon, TN 2016 current Originally designated SR 840 until completion
I-244 20 32 I-270/I-55 in Mehlville, MO I-270/I-70 in Bridgeton, MO — — Redesginated as I-270 in the late-1970s for consistency along the St. Louis Beltway
I-244 15.75 25.35 I-44 in Tulsa, OK I-44 in Tulsa, OK 1970 current
I-344 29.4 47.3 I-240 in Oklahoma City, OK I-35 and I-44/Turner Turnpike in Oklahoma City, OK 2024 current Routed along the John Kilpatrick Turnpike
I-444 2.51 4.04 I-244 in Tulsa, OK I-244 in Tulsa, OK 1970 current Unsigned
I-345 1.40 2.25 I-30/I-45 in Dallas, TX US 75 in Dallas, TX 1973 current Unsigned
I-555 49.80 80.15 I-55 in Turrell, AR AR 91 in Jonesboro, AR 2016 current
I-155 32.13 51.71 I-55 in Lincoln, IL I-74 in Morton, IL 1992 current
I-255 30.82 49.60 I-55/I-270 in Mehlville, MO I-270/IL 255 in Pontoon Beach, IL 1986 current
I-355 32.51 52.32 I-80 in New Lenox, IL I-290 in Itasca, IL 1989 current
I-155 15.93 25.64 I-55 near Hayti, MO US 51 at Dyersburg, TN 1980 current
I-255 — — I-55/I-240 in Memphis, TN I-40 in Memphis, TN — — Now part of I-55 and I-240
I-359 2.30 3.70 I-20/I-59 in southern Tuscaloosa, AL 15th Street in downtown Tuscaloosa, AL 1983 current
I-459 32.80 52.79 I-20/I-59 in Bessemer, AL I-59 in Trussville, AL 1984 current
I-759 4.50 7.24 I-59 in Attalla, AL US 411/SR 759 in Gadsden, AL 1986 current
I-164 21.39 34.42 US 41/Veterans Memorial Parkway in Evansville, IN I-69 in Evansville, IN 1990 2014 Decommissioned; now part of I-69
I-264 22.93 36.90 I-64 in Louisville, KY I-71 in Louisville, KY 1956 current
I-264 25.07 40.35 I-64/I-664 in Chesapeake, VA Parks Ave in Virginia Beach, VA 1960 current
I-464 4.71 7.58 I-64 in Chesapeake, VA I-264 in Norfolk, VA 1960 current
I-564 3.03 4.88 SR 337 I-64 in Norfolk, VA 1970 current
I-664 20.21 32.52 I-64/I-264 in Norfolk, VA I-64 in Hampton, VA 1971 current
I-165 4.90 7.89 US 43 in Mobile, AL I-65 in Mobile, AL 1994 current
I-565 21.40 34.44 I-65/US 72/SR 20 in Decatur, AL US 72 in Huntsville, AL 1991 current
I-265 2 3 I-40 in Nashville, TN I-65 in Nashville, TN — 2000 Now part of I-65
I-165 69.684 112.146 I-65 in Bowling Green, KY US 60/US 231 in Owensboro, KY 2019 current Replaced the William H. Natcher Parkway; originally designated as I-66 Spur in 2008 followed by I-65 Spur in 2015
I-365 88 142 I-65 near Park City, KY US 27 in Somerset, KY proposed — Future designation along the Cumberland Parkway
I-165 2.70 4.35 I-65/I-70 in Indianapolis, IN 38th Street in Indianapolis, IN 1978 1981 Was to be a spur linking from I-65/70 to 38th Street entirely with Indianapolis
I-265 31.21 50.23 I-64/US 150/SR 62 in New Albany, IN I-65/I-265/KY 841 in Heritage Creek, KY 1977 current Completed on December 18, 2016, with the completion of the East End Bridge that connected the Indiana segment to the Kentucky segment
I-465 52.79 84.96 Beltway around Indianapolis 1970 current
I-865 4.72 7.60 I-65 near Indianapolis, IN I-465 near Indianapolis 2002 current

Lua error in Module:Routelist_row at line 277: Type not in database: I-Spur.
I-266 1.79 2.88 I-66 in Arlington, Virginia I-66 in Washington, D.C. — 1972 Proposed loop route of I-66 between the District, and Arlington County; if built, would have been the only auxiliary route of I-66; canceled in the face of community opposition during Washington's freeway revolts
I-169 34.27 55.15 I-24 near Hopkinsville, KY I-69 in Nortonville, KY 2017 current New designation along the former Pennyrile Parkway; currently unsigned pending upgrade to Interstate standards
I-369 23.441 37.725 I-69/Pennyrile Parkway in Henderson, KY US 60 in Owensboro, KY proposed — Proposed for designation along Audubon Parkway once upgraded to Interstate standards
I-569 38.446 61.873 I-69/I-169 in Nortonville, KY I-165 in Beaver Dam, KY proposed — Future designation for the western part of Western Kentucky Parkway once upgraded to Interstate standards
I-269 45.19 72.73 I-55/I-69/MS 304 in Hernando, MS I-40/SR 385 in Arlington, TN 2015 current Construction completed in October 2018; co-signed with SR 304 in Mississippi; extension to Millington, TN to connect with the proposed I-69 extension planned
I-169 18.7 30.1 US 45W/US 51 in Union City, TN US 45E/SR 43 in Martin, TN proposed — Proposed for designation along SR 22 once upgraded to Interstate standards
I-469 30.83 49.62 I-69 in Fort Wayne, IN I-69 in Fort Wayne, IN 1995 current
I-169 1.50 2.41 Port of Brownsville main entrance in Brownsville, TX I-69E/US 77/US 83 in Olmito, TX 2015 current Currently under construction; partially open and co-signed with SH 550
I-369 3.50 5.63 I-30/US 59 in Texarkana, TX US 59/SH 93 in Texarkana, TX 2013 current Partially completed in 2013
I-270 5.31 8.55 I-25/US 36 at Welby, CO I-70/US 36 at Denver, CO 1965 current
I-470 — — Beltway around Denver Metro, CO — — Northwestern portion cancelled due to local opposition; completed segments are designated as SH 470 or E-470
I-270 50.59 81.42 I-55/I-255 in Mehlville, MO I-55/I-70 near Troy, IL 1956 current
I-470 13.72 22.08 I-70 in Topeka, KS I-70/Kansas Turnpike in Topeka, KS 1960 current
I-670 2.81 4.52 I-70 in Kansas City, KS I-70 in Kansas City, MO 1968 current
I-170 2.30 3.70 I-70 in Baltimore, MD US 40 in Baltimore, MD 1969 1983 Canceled
I-270 32.60 52.46 I-70 near Frederick, MD I-495 north of Bethesda, MD 1975 current

I-270 Spur		 2.10 3.38 I-270 east of Potomac, MD I-495 northwest of Bethesda, MD 1975 current Serves as an alternate connector for Virginia travelers
I-370 2.54 4.09 I-270 in Gaithersburg, MD MD 200 in Derwood, MD 1988 current
I-170 11.17 17.98 I-64/US 40 in Richmond Heights, MO I-270 in Hazelwood, MO 1956 current
I-470 16.72 26.91 I-49/I-435 in Kansas City, MO I-70 in Independence, MO 1983 current
I-270 54.97 88.47 Beltway around Columbus, OH 1964 current
I-470 6.69 10.77 I-70 near Blaine, OH I-70 in Elm Grove, WV 1976 current
I-670 9.37 15.08 I-70 in Columbus, OH I-270 near John Glenn Columbus International Airport 2003 current
I-271 46.06 74.13 I-71 near Medina, OH I-90 in Willoughby Hills, OH 1964 current
I-471 5.75 9.25 I-275 near Newport, KY I-71 in Cincinnati, OH 1981 current
I-172 19.69 31.69 I-72 in Quincy, IL US 24 in Quincy, IL 1995 current
I-474 14.88 23.95 I-74 in Peoria, IL I-74 in Morton, IL 1973 current
I-274 16.83 27.09 US 158 near Clemmons, NC Future I-74/Future I-285/US 52 in Bethania, NC proposed — Proposed route in Winston-Salem, NC
I-175 1.44 2.32 I-275 in St. Petersburg, FL SR 687 in St. Petersburg, FL 1980 current
I-275 60.64 97.59 I-75 near Memphis, FL I-75 in Wesley Chapel, FL 1973 current
I-375 1.34 2.16 I-275 in St. Petersburg, FL US 92 in St. Petersburg, FL 1979 current
I-175 — — US 82 in Albany, GA I-75 in Cordele, GA — — Now part of SR 300
I-475 15.83 25.48 I-75 in Macon, GA I-75 in Macon, GA 1965 current
I-575 30.97 49.84 I-75 in Kennesaw, GA SR 5 west of Nelson, GA 1985 current
I-675 11.04 17.77 I-75 in Stockbridge, GA I-285 southeast of Atlanta, GA 1987 current
I-275 83.71 134.72 Beltway around Cincinnati, OH 1962 current Runs through Indiana, Ohio and Kentucky; I-75 does not run through Indiana
I-275 35.01 56.34 I-75 near Monroe, MI I-96, I-696 and M-5 in Farmington Hills, MI 1977 current
I-375 1.06 1.71 BS I-375 in Detroit, MI I-75 in Detroit, MI 1964 current Will be downgraded to a boulevard starting in 2025
I-475 16.99 27.34 I-75 near Grand Blanc, MI I-75/US 23 near Mount Morris, MI 1973 current Runs east and north of Flint, MI
I-675 7.72 12.42 I-75/US 23 near Saginaw, MI I-75/US 23 near Zilwaukee, MI 1971 current
I-475 20.37 32.78 I-75 in Perrysburg, OH I-75 in Toledo, OH 1964 current
I-675 26.53 42.70 I-75 near Miamisburg, OH I-70 near Medway, OH 1987 current
I-175 — — I-75 in Chattanooga, TN I-75 in Lexington, KY — —
I-275 2.98 4.80 I-40 in Knoxville, TN I-75/I-640 in Knoxville, TN 1982 current
I-475 — — I-40/I-75 near Knoxville, TN I-75 near Knoxville, TN 1990 — Canceled due to local opposition and high construction costs
I-676 6.90 11.10 I-76/US 30 in Philadelphia, PA I-76 in Camden, NJ 1991 current
I-176 11.33 18.23 I-76/Pennsylvania Turnpike in Morgantown, PA US 422 near Reading, PA 1964 current
I-276 29.78 47.93 I-76 in King of Prussia, PA I-95/I-295 in Bristol Township, PA 1964 current
I-376 84.42 135.86 I-80 near Hermitage, PA I-76/US 22 in Monroeville, PA 1972 current
I-476 129.61 208.59 I-95 near Chester, PA I-81/US 6/US 11 near Clarks Summit, PA 1992 current
I-876 1.57 2.53 PA 885 in Pittsburgh, PA I-279/PA 28 in Pittsburgh, PA 1970 1971 Short lived renumbering of I-479, now I-579
I-277 4.46 7.18 I-77/US 21/US 74/NC 27 in Charlotte, NC I-77/US 21/NC 16 in Charlotte, NC 1981 current Partial loop around Uptown Charlotte
I-277 4.14 6.66 I-76 in Akron, OH I-77 in Akron, OH 1970 current
I-178 — — — — — 1971 Canceled
I-378 — — — — 1968 1971 Replaced by PA Route 378
I-278 35.62 57.32 US 1/9 in Linden, NJ Bruckner Interchange in Bronx, NY 1961 current Does not intersect with parent route I-78
I-478 2.14 3.44 I-278 in Brooklyn, NY NY 9A in Manhattan, NY 1971 current Unsigned; does not intersect with parent route I-78
I-678 14.33 23.06 John F. Kennedy International Airport in Queens, NY Bruckner Interchange in Bronx, NY 1965 current Does not intersect with parent route I-78
I-878 0.70 1.13 I-678 in Queens, NY, near John F. Kennedy International Airport JFK Expressway in Queens, NY, near JFK Airport 1970 current Unsigned; does not intersect with parent route I-78; eastbound only
I-179 — — McKean Township, PA Erie, PA 1958 1968 Replaced by its parent route, I-79
I-279 13.32 21.44 I-376/US 22/US 30 in Pittsburgh, PA I-79 in Franklin Park, PA 1972 current
I-479 1.57 2.53 PA 885 in Pittsburgh, PA I-279/PA 28 in Pittsburgh, PA 1966 1970 Early number for I-579
I-579 1.57 2.53 PA 885 in Pittsburgh, PA I-279/PA 28 in Pittsburgh, PA 1971 current
I-180 — — US 101 in San Rafael, CA I-80 near Berkeley, CA 1978 1991 Temporary designation of what was formerly part of SR 17, now part of I-580
I-280 57.22 92.09 I-680/US 101 in San Jose, CA King Street in San Francisco, CA 1964 current
I-238 2.23 3.59 I-880 in San Leandro, CA I-580/SR 238 in Castro Valley, CA 1983 current Considered an auxiliary route of I-80 in California; there is no I-38
I-380 1.671 2.689 I-280 in San Bruno, CA US 101 in San Bruno, CA 1964 current
I-480 — — I-80 in San Francisco, CA Sansome Street in San Francisco, CA 1957 1968 Was to be the Embarcadero Freeway; downgraded to a state highway in 1968 and fully decommissioned in 1991
I-580 75.63 121.71 US 101 in San Rafael, CA I-5 near Westley, CA 1964 current Segments were originally part of I-5W
I-680 70.52 113.49 I-280/US 101 in San Jose, CA I-80 in Cordelia, CA 1955 current Originally SR 21
I-780 6.50 10.46 I-80 in Vallejo, CA I-680 in Benicia, CA 1955 current Originally part of I-680
I-880 47.22 75.99 I-280/SR 17 in San Jose, CA I-80/I-580 in Oakland, CA 1983 current Originally part of SR 17
I-880 — — I-80 in West Sacramento, CA I-80 in Sacramento, CA 1971 1983 Now part of I-80
I-980 2.03 3.27 I-880 in Oakland, CA I-580/SR 24 in Oakland, CA 1981 current
I‑580 30.09 48.43 US 50 in Carson City, NV I-80 in Reno, NV 2012 current Runs concurrently with US 395
I-180 13.19 21.23 IL 26/IL 71 in Hennepin, IL I-80 near Princeton, IL 1969 current
I-280 26.98 43.42 I-80 near Davenport, IA I-74/I-80 near Colona, IL 1990 current
I-380 73.05 117.56 I-80 near Iowa City, IA US 218 in Waterloo, IA 1985 current Connects Waterloo and Cedar Rapids, IA, with I-80
I-480 4.90 7.89 I-80/US 75 in Omaha, NE I-29/US 6 in Council Bluffs, IA 1966 current
I-680 16.49 26.54 I-80 in Omaha, NE I-29 near Crescent, IA 1966 current
I-880 16.57 26.67 I-29 near Loveland, IA I-80 near Neola, IA 2019 current Former section of I-680
I-180 3.18 5.12 US 34 in Lincoln, NE I-80/US 34/US 77 in Lincoln, NE 1965 current
I-280 — — I-80 in Omaha, NE I-29 near Crescent, IA 1958 1965 Redesignated as I-680 due to the I-280 already being planned in the Davenport, Iowa area
I-580 1.60 2.57 I-480 in Omaha, NE Lake Street in Omaha, NE 1976 1982 Now part of US 75 due to the I-480 interchange not being up to interstate standards
I-280 17.85 28.73 I-80 in Parsippany-Troy Hills, NJ I-95/New Jersey Turnpike in Kearny, NJ 1958 current
I-280 12.41 19.97 I-80/I-90/Ohio Turnpike in Lake Township, OH I-75 in Toledo, OH 1959 current
I-380 — — I-76/I-77 in Akron, OH I-271 in Macedonia, OH proposed — Proposed designation for SR 8 between Akron and Macedonia
I-480 41.77 67.22 I-80/Ohio Turnpike in North Ridgeville, OH I-80/Ohio Turnpike in Streetsboro, OH 1971 current
I-680 16.43 26.44 I-76/Ohio Turnpike in North Lima, OH I-80/SR 11 near Mineral Ridge, OH 1964 current
I-180 28.85 46.43 US 15/US 220 in Williamsport, PA I-80/PA 147 near Milton, PA 1984 current
I-180 — — — — — 1964 Original number for I-176 when I-76 was I-80S
I-280 — — — — 1958 1964 Now part of Pennsylvania Turnpike
I-380 24.76 39.85 I-80 in Tunkhannock Township, PA I-81/I-84/US 6 in Dunmore, PA 1973 current
I-480 — — — — 1958 1964 Early number for I-476 when I-76 was I-80S
I-680 — — — — 1958 1964 Original number for I-676 when I-76 was I-80S
I-180 1.09 1.75 I-80 in Cheyenne, WY I-80 Bus./US 30 in Cheyenne, WY 1984 current Built as a boulevard, not to Interstate Highway standards
I-281 9.45 15.21 I-81 in Onondaga, NY New York State Thruway (I-90) in DeWitt, NY — 1970 Redesignated as I-481 on January 1, 1970
I-481 15.04 24.20 I-81 in Onondaga, NY I-81/NY 481 in North Syracuse, NY 1970 current Will be decommissioned when I-81 is rerouted onto the freeway and the original I-81 routing becomes I-81 Business
I-781 4.30 6.92 I-81 in Pamelia, NY Fort Drum main gate in Le Ray, NY 2012 current
I-381 1.67 2.69 SR 381 in Bristol, VA I-81 in Bristol, VA 1961 current
I-581 6.64 10.69 US 220/SR 24 in Roanoke, VA I-81 near Hollins, VA 1955 current
I-181 23.85 38.38 US 321/SR 67 in Johnson City, TN US 11W/SR 1 in Kingsport, TN 1985 2007 Now part of I-26
I-182 15.19 24.45 I-82/US 12 near Richland, WA US 12/US 395 in Pasco, WA 1969 current Completely concurrent with US 12
I-283 2.91 4.68 I-76/Pennsylvania Turnpike near Highspire, PA I-83/US 322/Capital Beltway near Harrisburg, PA 1972 current
I-184 3.62 5.83 I-84 in Boise, ID US 20/US 26 in Boise, ID 1990 current
I-384 8.20 13.20 I-84/US 6 in East Hartford, CT US 6/US 44 in Bolton, CT 1984 current
I-684 28.47 45.82 I-287 near White Plains, NY NY 22 near Brewster, NY 1974 current Original routing of I-87; also crosses into Connecticut
I-685 14.00 22.53 I-65 in downtown Montgomery, AL I-85 in Montgomery, AL proposed — Future designation for I-85 in Montogomery once the Montgomery Outer Loop is completed and I-85 is routed onto it
I-185 49.30 79.34 US 27/US 280/SR 520 in Columbus, GA I-85 near LaGrange, GA 1979 current
I-285 63.98 102.97 Beltway around Atlanta, GA 1969 current
I-485 5.9 9.5 I-75/I-85 in Atlanta, GA I-85 in Atlanta, GA 1964 1975 Completed section now the Freedom Parkway, was planned to relieve traffic along Downtown Connector (I-75/85) through downtown Atlanta
I-985 24.04 38.69 I-85 near Buford, GA SR 369 near Gainesville, GA 1985 current
I-285 22.8 36.7 I-85/I-85 Bus./US 29/US 52/US 70 near Lexington, NC I-40/US 52/US 311/NC 8 in Winston-Salem, NC 2018 current An unconfirmed section of Future I-285 is to continue north of I-40 for 10 miles (16 km) along US 52, through downtown Winston-Salem, to the proposed Winston-Salem Northern Beltway.
I-485 66.68 107.31 Beltway around Charlotte, NC 1988 current
I-685 — — Greensboro, NC Dunn, NC proposed — Future designation that will run concurrently with US 421 once the latter route is upgraded to interstate standards
I-785 2.21 3.56 I-40/I-85/I-840/I-85 Bus. in Greensboro, NC US 70 in Greensboro, NC 2013 current Future northern terminus at US 29/US 58/US 360/US 58 Bus. in Danville, VA
I-885 8.566 13.786 I-40/NC 885 in Research Triangle Park, NC I-85/US 70/US 15 in Durham, NC 2022 current
I-185 17.70 28.49 I-385 near Mauldin, SC US 29 in Greenville, SC 1955 current
I-385 42.16 67.85 I-26 near Clinton, SC US 276 in Greenville, SC 1962 current
I-585 2.25 3.62 US 176/US 221/SC 9 in Spartanburg, SC I-85 Bus./US 176 near Spartanburg, SC 1962 current Does not connect to I-85
I-587 55.9 90.0 I-87/US 64 near Zebulon, NC US 264 near Greenville, NC 2022 current Former section of US 264; does not currently connect to I-87
I-287 98.72 158.87 I-95/New Jersey Turnpike/Route 440 in Edison, NJ I-95 in Rye, NY 1961 current
I-187 — — I-287/New York State Thruway in Greenburgh, NY I-95 in Rye, NY 1957 1958 Original designation for the Cross-Westchester Expressway; it was signed as I-487 when it opened
I-487 — — I-287/New York State Thruway in Greenburgh, NY I-95 in Rye, NY 1958 1961 Original signed designation for the Cross-Westchester Expressway; it was replaced by an extension of I-287
I-487 — — I-87/I-287/New York State Thruway in Tarrytown, NY I-84 in Beacon, NY 1965 1971 Known as the Hudson River Expressway; the project was cancelled and the only portion to be constructed and opened is now the Croton Expressway
I-587 1.21 1.95 I-87/New York State Thruway/NY 28 in Kingston, NY NY 28/NY 32 in Kingston, NY 1960 current
I-687 9.10 14.65 I-90/New York State Thruway in Colonie, NY I-90 in Albany — 1973 Also known as the Albany Airport Connector; the project was cancelled in the face of local opposition
I-787 10.16 16.35 I-87/New York State Thruway in Albany, NY NY 7 in Green Island, NY 1968 current
I-189 1.49 2.40 US 7 in South Burlington, VT I-89 in South Burlington, VT 1980 current
I-190 3.07 4.94 O'Hare International Airport in Chicago, IL I-90 in Chicago, IL 1978 current
I-290 29.84 48.02 I-90/IL 53 in Rolling Meadows, IL I-90/I-94/Ida B. Wells Drive in Chicago, IL 1972 current
I-490 — — I-294 in Franklin Park, IL I-90 in Des Plaines, IL proposed — Proposed route number for the O'Hare West Bypass
I‑190 19.26 31.00 I-290 in Worcester, MA Route 2 in Leominster, MA 1983 current
I‑290 20.16 32.44 I-395 in Auburn, MA I-495 in Marlborough, MA 1970 current
I-190 28.34 45.61 I-90/New York State Thruway in Cheektowaga, NY Highway 405 at Lewiston, NY 1959 current
I-290 9.80 15.77 I-190 in Tonawanda, NY I-90/New York State Thruway in Williamsville, NY 1964 current
I-390 76.06 122.41 I-86/NY 17 in Avoca, NY I-490 in Gates, NY 1973 current
I-490 37.40 60.19 I-90/New York State Thruway in Bergen, NY I-90/New York State Thruway in Victor, NY 1970 current
I-590 5.31 8.55 I-390 in Brighton, NY I-490/NY 590 in Rochester, NY 1980 current
I-690 14.19 22.84 I-90/New York State Thruway/NY 690 in Van Buren, NY I-481 in East Syracuse, NY 1962 current
I-790 2.41 3.88 I-90/New York State Thruway in Deerfield, NY NY 5A/NY 55 in Utica, NY 1961 current
I-890 9.35 15.05 I-90/New York State Thruway in Rotterdam, NY I-90/New York State Thruway in Guilderland, NY 1962 current
I-990 6.35 10.22 I-290 in Amherst, NY NY 263 near Lockport, NY 1985 current Highest numbered Interstate in the Interstate system
I-490 2.43 3.91 I-71/I-90 in Cleveland, OH East 55th Street in Cleveland, OH 1990 current
I-190 1.72 2.77 I-90 in Rapid City, SD US 16 in Rapid City, SD 1962 current
I-291 6.02 9.69 I-91 in Windsor, CT I-84 in Manchester, CT 1994 current
I-691 8.38 13.49 I-84 at the Southington-Cheshire, CT town line I-91 in Meriden, CT 1988 current
I‑291 5.44 8.75 I-91 in Springfield, MA I-90/Massachusetts Turnpike in Chicopee, MA 1972 current
I‑391 4.46 7.18 I-91 in Chicopee, MA High Street in Holyoke, MA 1970 current
I-293 11.18 17.99 I-93/NH 101 in Manchester, NH I-93/Everett Turnpike in Hooksett, NH 1976 current
I-393 4.60 7.40 I-93 in Concord, NH NH 9 in Pembroke, NH 1979 current
I-294 53.42 85.97 I-80/I-94 in South Holland, IL I-94 in Deerfield, IL 1968 current
I-194 3.38 5.44 I-94 in Battle Creek, MI M-66 in Battle Creek, MI 1961 current
I-394 9.75 15.69 I-494/US 12 in Minnetonka, MN 4th Street in Minneapolis, MN 1991 current
I-494 42.94 69.11 I-94/I-694 in Maple Grove, MN I-94/I-694 in Woodbury, MN 1985 current Western and southern half of the Minneapolis–St. Paul beltway
I-694 30.77 49.52 I-94/I-494 in Maple Grove, MN I-94/I-494 in Woodbury, MN 1970 current Northern and eastern half of the Minneapolis–St. Paul beltway
I-194 1.20 1.93 McKenzie Drive near Bismarck, ND I-94 near Mandan, ND 1958 current Unsigned
I-794 3.75 6.04 I-43/I-94 in Milwaukee, WI WIS 794 in Milwaukee, WI 1980 current
I-894 4.70 7.56 I-41/I-94 in Milwaukee, WI I-41/I-43/I-94 in Milwaukee, WI 1966 current Completely concurrent with I-41
I-395 66.60 107.18 I-95 in East Lyme, CT I-290 in Auburn, MA 1983 current
I-295 92.30 148.54 I-95/I-495 in New Castle, DE I-95 in Bristol Township, PA 1994 current Extended into Pennsylvania in 2018
I-495 11.47 18.46 I-95/I-295 in Newport, DE I-95 in Lower Chichester Township, PA 1977 current
I-895 10.78 17.35 Newport, Delaware Claymont, Delaware 1979 1980 Now part of I-95
I-195 2.41 3.88 I-395 in Washington D.C. US 50 in Washington D.C. proposed — Currently I-395; I-395 will be rerouted onto I-695
I-395 13.39 21.55 I-95/I-495 in Springfield, VA US 50 in Washington, DC 1977 current Original route of I-95 that was proposed to continue through Washington, DC
I-495 64 103 Beltway around Washington, DC 1961 current Capital Beltway; runs through Virginia, Maryland and a small sliver of Washington, DC, over the Wilson Bridge
I-695 2.00 3.22 I-395 in Washington, DC I-295 in Washington, DC 1958 current Unsigned until 2011; future plans call for the route number to be replaced by an extension of I-395
I-195 4.42 7.11 I-95/SR 112 in Miami, FL SR 905 in Miami Beach, FL 1961 current
I-295 61.04 98.23 Beltway around Jacksonville, FL 1970 current
I-395 1.29 2.08 I-95 in Miami, FL MacArthur Causeway at Watson Island, Miami, FL 1971 current
I-595 12.86 20.70 I-75/SR 869 in Weston, FL US 1 in Fort Lauderdale, FL 1990 current
I-795 7.4 11.9 I-95 south of Jacksonville, FL I-295 in Jacksonville, FL proposed — Currently signed as SR 9B pending approval of the interstate designation from the AASHTO
I-195 1.55 2.49 I-95/Maine Turnpike in Saco, ME SR 5 in Saco, ME 1980 current
I-295 53.11 85.47 I-95/Maine Turnpike in Scarborough, ME I-95/Maine Turnpike in Gardiner, ME 1960 current
I-395 4.99 8.03 I-95/US 2/SR 100 in Bangor, ME US 1A in Brewer, ME 2008 current
I-495 3.70 5.95 I-95/Maine Turnpike in Portland, ME I-295/US 1 in Falmouth, ME 2004 current Unsigned
I-195 4.71 7.58 I-95/MD 166 near Catonsville, MD Baltimore-Washington International Airport 1990 current
I-395 1.98 3.19 I-95 in South Baltimore, MD West Pratt Street in Baltimore, MD 1981 current
I-595 19.97 32.14 I-95/I-495/US 50 near Washington, DC US 50/US 301/MD 70 in Annapolis, MD 2011 current Unsigned designation for US 50
I-695 30.57 49.20 Beltway around Baltimore, MD 1958 current
I-795 8.99 14.47 I-695 in Pikesville, MD MD 140 in Reisterstown, MD 1985 current
I-895 11.44 18.41 I-95 near Elkridge, MD I-95 in Baltimore, MD 1979 current
I-295 8.05 12.96 I-95/I-495 near Forest Heights, MD I-695 in Washington, DC 1964 current
I‑195 44.55 71.70 I-95 in Providence, RI I-495/Route 25 in Wareham, MA 1958 current
I‑295 26.58 42.78 I-95 in Warwick, RI I-95 in Attleboro, MA 1969 current
I‑495 121.56 195.63 I-195/Route 25 in Wareham, MA I-95 in Salisbury, MA 1957 current
I‑695 — — I-95 in Roxbury, MA I-93 in Charlestown, MA 1955 1971 Canceled; was to have been built in connection with a planned alignment of I-95 through downtown Boston
I‑895 — — Route 37/I-295 in Cranston, RI I-95/I-295 in Attleboro, MA 1968 1982 Canceled; would have supplemented I-295 to create a full Beltway around Providence, RI
I-195 34.17 54.99 I-295 in Hamilton Township, NJ Route 34 in Wall Township, NJ 1968 current
I-895 — — I-295 in Burlington, NJ I-95 in Bristol, PA 1963 1981 Never built
I-295 9.79 15.76 NY 25/NY 24 in Queens, NY Bruckner Interchange in Bronx, NY 1970 current
I-495 71.02 114.30 Queens Midtown Tunnel in Manhattan, NY CR 58 in Riverhead, NY 1958 current
I-695 1.77 2.85 I-95 in Bronx, NY I-295 in Bronx, NY 1986 current
I-895 1.12 1.80 I-278 in Bronx, NY I-95 in Bronx, NY 1970 2017 Downgraded to a boulevard and designated as NY 895
I-295 34.0 54.7 Cliffdale Road in Fayetteville, NC I-95 and US 13 near Eastover, NC 2019 current Unfinished Fayetteville Outer Loop; expected to be completed in its entirety in Summer 2026
I-495 4.10 6.60 I-440/US 64/US 64 Bus. in Raleigh, NC I-540/US 64/US 264 in Knightdale, NC 2013 2017 Now part of I-87
I-795 25.46 40.97 US 70/US 117 in Goldsboro, NC I-95/US 264 in Wilson, NC 2007 current
I-695 — — I-95 near Philadelphia International Airport I-95 in Philadelphia, PA 1964 1977 Never built
I-195 3.24 5.21 SR 195 in Richmond, VA I-64/I-95 in Richmond, VA 1970 current
I-295 52.56 84.59 I-95 near Petersburg, VA I-64 near Short Pump, VA 1980 current
I-595 — — I-395 near Arlington, VA US 1 at Ronald Reagan Washington National Airport — — Now part of US 1
I-895 — — I-95 near Richmond, VA I-295 near Richmond, VA 1996 2002 Currently designated as SR 895, it was originally planned as an Interstate designation, but did not get approved by AASHTO
I-495 — — — — 1956 1958 Early number of I-476
I-196 37.07 59.66 US 31 in Norton Shores, MI I-96/US 16 in Grand Rapids, MI 1959 1963 Now the western end of I-96
I-196 80.65 129.79 I-94/US 31 near Benton Harbor, MI I-96/M-37 in Grand Rapids, MI 1963 current
I-296 3.43 5.52 I-196 in Grand Rapids, MI I-96/M-37 in Walker, MI 1962 current Unsigned since 1979
I-496 11.78 18.96 I-69/I-96 near Lansing, MI I-96 and US 127 near Lansing, MI 1970 current
I-696 29.39 47.30 I-96/I-275 & M-5 in Novi, MI I-94 in Roseville, MI 1989 current
I-197 3.44 5.54 — — — c. 1980 Replaced by I-595
I-297 — — — — — 1987 Withdrawn from request, replaced by MD 3
  •       Former
  •       Future

See also

kids search engine
All content from Kiddle encyclopedia articles (including the article images and facts) can be freely used under Attribution-ShareAlike license, unless stated otherwise. Cite this article:
List of auxiliary Interstate Highways Facts for Kids. Kiddle Encyclopedia.