US Interstate Highways

## US Interstate Highway System

The US Interstate Highway system is a system of controlled-access highways that run throughout the contiguous United States and on Hawaii. Interstate Highways provide quick routes for car travel throughout the country, and all major American cities are served by at least 1 Interstate Highway. Construction of the Interstate Highways began under president Dwight Eisenhower in 1956.

### Numbering

Interstate Highways are numbered corresponding to their direction, length, and whether they provide a major cross-country route or a bypass or spur. Long-distance major arteries that run east to west are all even numbers, with the longest ending in zeroes. Smaller but still major east-west interstates have even numbers such as 2, 4, 6 or 8.

Similarly, Interstates that run north to south are labelled as odd numbers. The longest north-south routes end in a 5, with other, smaller north-south highways ending in various other odd numbers, usually 3 or 7.

Auxiliary Interstates are labelled with 3 digits to distinguish them from their parent routes. These interstates can be circumfrential, radial, or spurs. Both circumfrential and radial Interstates return to the parent, and always begin with an even number. Spurs do not return to the parent highway or another Interstate and end into another non-interstate highway such as a state route, or into surface roads.

## List of US Interstates.

* Interstate 4 - Florida
	+ Tampa Bay
	+ Orlando
	+ Daytona Beach
* Interstate 5 - California, Oregon, Washington
	+ San Diego
	+ Anaheim
	+ Sacaramento
	+ Portland
	+ Olympia
	+ Seattle
* Interstate 8 - California, Arizona
	+ San Diego
	+ Mexicali
	+ Phoenix
* Interstate 10 - CA, AZ, NM, TX, LA, MS, AL, FL
	+ Anaheim/Santa Monica
	+ Phoenix
	+ Tucson
	+ El Paso
	+ Austin
	+ Houston
	+ New Orleans
	+ Mobile
	+ Jacksonville
* Interstate 12 - Bypass of New Orleans, LA
* Interstate 15 - CA, NV, AZ, UT, ID, MT
	+ San Diego
	+ Anaheim
	+ Las Vegas
	+ Salt Lake City
	+ Idaho Falls
	+ Canadian Border - Assiniboia
* Interstate 16 - GA
	+ Macon
	+ Savannah
* Interstate 17 - AZ
	+ Phoenix
	+ Interstate 40
* Interstate 19
	+ Tucson
	+ Sinaloa
	+ Mexican border
* Interstate 20 - SC, GA, AL, MS, LA, TX
	+ Columbia
	+ Atlanta
	+ Birmingham
	+ Jackson
	+ Shreveport
	+ Dallas
	+ El Paso
* Interstate 22 - MS, AL
	+ Memphis
	+ Birmingham
* Interstate 24 - IL, KY, TN, GA
	+ St. Louis
	+ Nashville
	+ Atlanta
* Interstate 25 - NM, CO, WY
	+ El Paso
	+ Albuquerque
	+ Colorado Springs
	+ Denver
	+ Fort Collins
	+ Cheyenne
* Interstate 26 - TN, NC, SC
	+ Charleston SC
	+ Columbia SC
	+ Bristol
* Interstate 29 - MO, IA, SD, ND
	+ Kansas City
	+ Omaha
	+ Sioux City
	+ Sioux Falls
	+ Fargo
* Interstate 30 - TX, AR
	+ Dallas
	+ Little Rock
* Interstate 35 - TX, OK, KS, MO, IA, MN
	+ Laredo/Mexican Border
	+ Austin
	+ Dallas
	+ Oklahoma City
	+ Kansas City
	+ Des Moines
	+ Minneapolis
	+ Duluth
* Interstate 37 - TX
	+ Austin
	+ Corpus Christi/Gulf Coast
* Interstate 40 - CA, AZ, NM, TX, OK, AR, TN, NC
	+ Anaheim
	+ Albuquerque
	+ Oklahoma City
	+ Little Rock
	+ Memphis
	+ Nashville
	+ Knoxville
	+ Asheville
	+ Raleigh
	+ Atlantic Ocean
* Interstate 41 - WI
	+ Milwaukee
	+ Appleton/Neenah
	+ Green Bay
* Interstate 43 - IL, WI
	+ Rockford IL
	+ Waukesha
	+ Milwaukee
	+ Sheboygan
	+ Manitowoc
	+ Green Bay
* Interstate 44 - TX, OK, MO
	+ St, Louis
	+ Springfield MO
	+ Joplin
	+ Tulsa
	+ Broken Arrow
	+ Oklahoma City
	+ Fort Sill
* Interstate 45 - TX - Dallas Hou connector
	+ Dallas
	+ Houston
	+ Galveston
* Interstate 49 - AR, MO
	+ Kansas City
	+ Fort Smith
* Interstate 55 - LA, MS, TN, AR, MO, IL
	+ Chicago
	+ St. Louis
	+ Memphis
	+ Jackson
	+ New Orleans
* Interstate 57 - MO, IL - St. Louis southern bypass
	+ Chicago
	+ Cape Girardeau MO
* Interstate 59 - LA, MS, AL, GA
	+ New Orleans
	+ Birmingham
	+ Chattanooga
* Interstate 64 - MO, IL, IN, KY, WV, VA
	+ St. Louis
	+ Evansville
	+ Louisville
	+ Lexington
	+ Charleston
	+ Richmond
	+ Norfolk
* Interstate 65
	+ Mobile
	+ Montgomery
	+ Birmingham
	+ Huntsville
	+ Nashville
	+ Louisville
	+ Indianapolis
	+ Chicago
* Interstate 66 - VA, DC
	+ Appalachian Mtns
	+ Washington DC
* Interstate 69 - TN, KY, IN, MI
	+ Memphis
	+ Evansville
	+ Indianapolis
	+ Fort Wayne
	+ Lansing
	+ Flint
	+ Canadian border
* Interstate 70 - UT, CO, KS, MO, IL, IN, OH, PA, MD
	+ Salt Lake City
	+ Denver
	+ Kansas City
	+ St. Louis
	+ Indianapolis
	+ Dayton
	+ Columbus
	+ Baltimore
* Interstate 71 - KY, OH
	+ Louisville
	+ Cincinnati
	+ Columbus
	+ Cleveland