List of Interstate Highways

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Interstate_Locations_Interstate_Highways_Blanding_Cassatt — Interstate Locations Interstate Highways Blanding Cassatt

The following is a list of 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-to-north, with lower numbers in the west and higher numbers in the east; whereas even-numbered Interstates run west-to-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 (for example: I-10 travels from Santa Monica, California, to Jacksonville, Florida, traveling from the Pacific to Atlantic oceans, while I-35 travels from Laredo, Texas to Duluth, Minnesota, traveling from the Mexican to Canadian borders). Additionally, auxiliary highways have their numbering system where a different number prefixes the number of its parent highway (for example: I-476 is an auxiliary route of I-76 in Pennsylvania, and I-710 is an auxiliary route of I-10 in California.

Five route numbers are duplicated in the system, though the corresponding highways are separated by state lines or regions of the United States which prevent confusion. These Interstates include:

I-76: One that goes from Denver, Colorado to Big Springs, Nebraska, and another one that goes from Westfield Center, Ohio to Bellmawr, New Jersey.
I-84: One that goes from Portland, Oregon to Echo, Utah, and another one that goes from Scranton, Pennsylvania to Sturbridge, Massachusetts.
I-86: One in Idaho that goes from Heyburn to Pocatello, and another one that goes from Erie, Pennsylvania to Windsor, New York.
I-87: One in North Carolina that currently goes from Raleigh to Wendell and is planned to extend north ending in Norfolk, Virginia, and another one in New York that goes from New York City to Champlain.
I-88: One in Illinois that goes from Barstow to Hillside, and another one in New York that goes from Binghamton to Schenectady.

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[]

Number	Miles (km)	Southern or western terminus	Northern or eastern terminus	Formed	Removed	States	Auxiliary routes
I-1	TBD	I-5 in Dana Point, CA	I-5 in Leggett, CA	TBD	Current	Intrastate, California only	None
I-2	46 (75)	US 83 in Penitas, TX	I-69E /US 77 /US 83 in Harlingen, TX	2013	Current	Intrastate, Texas only	None
I-3	TBD	US 17 in Savannah, GA	I-40 in Knoxville, TN	TBD	Proposed	4 states: GA, SC, NC, and TN	None
I-4	132 (212)	I-275 in Tampa, FL	I-95/FL 400 in Daytona Beach, FL	1959	Current	Intrastate, Florida only	I-404
I-5	1,381 (2,222)	MX-1 at Mexico border in San Ysidro, CA	BC-99 at Canada border in Blaine, WA	1956	Current	3 states: CA, OR, and WA	I-105, I-205, I-305, I-405, I-505, I-605, I-705, I-805, I-905
I-7	TBD	MX-9 at Mexico border in Calexico, CA	I-40 in Kelso, CA	TBD	Current	Intrastate, California only	None
I-8	348 (560)	Sunset Cliffs Boulevard/Nimitz Boulevard in San Diego, CA	I-10 in Casa Grande, AZ	1964	Current	2 States: CA and AZ	None
I-10	2,460 (3,959)	I-1/CA 1 in Santa Monica, CA	I-95/US 17/FL 228 in Jacksonville, FL	1957	Current	10 states: CA, AZ, NM, TX, LA, MS, AL, and FL	I-110, I-210, I-310, I-410, I-510, I-610, I-710, I-810, I-910
I-11	23 (37)	US Route 93 at the Arizona State Line	Interstate 215/Interstate 515/US 93/US 95/SR 564 in Henderson	2017	Current	1 state (Nevada)	None
I-12	87 (140)
I-14	25 (40)
I-15	1,434 (2,308)	I-8 / SR 15 in San Diego,	Hwy 4 at Sweetgrass–Coutts Border Crossing at Sweet Grass, MT
I-16
I-17
I-18
I-19
I-20	1,539 (2,477)	Interstate 10 in Scroggins Draw, Texas	Interstate 95 near Florence, South Carolina	1957	Current	6 States: TX, LA, MS, AL, GA, SC	I-220, I-520, I-820
I-21	TBD
I-22
I-23	TBD
I-24
I-25
I-26
I-27
I-29
I-30
I-35
I-37
I-39
I-40
I-41
I-42
I-43
I-44
I-45
I-48	TBD
I-49
I-50	TBD
I-53	TBD
I-55
I-57
I-59
I-60	TBD
I-64
I-65
I-66
I-68
I-69
I-70
I-71
I-72
I-73
I-74
I-75
I-76
I-76
I-77
I-78
I-79
I-80
I-81
I-82
I-83
I-84
I-84
I-85
I-86
I-86
I-87
I-87
I-88
I-88
I-89
I-90
I-91
I-92	TBD
I-93
I-94
I-95
I-96
I-97
I-99
I-101	TBD

Outside of the contiguous United States[]

Hawaii[]

Alaska[]

Puerto Rico[]

Sintopia[]

The Sintopian Interstate Highway System (SIHS) is a system of completely controlled-access Interstate Highways designated in the U.S. state of Sintopia. They are fully maintained by Sintopia Department of Transportation (SDOT). These highways are designed uniquely and originally in different colors based on the Shoulder lanes and the Interstate shields in order to distinguish them from the regular designed Interstate shields in the other 50 states. However, SDOT is currently planning to put up standard, regular designed Interstate shields designated with the letter S for Sintopia before the numbers. Sintopian Interstate Highways are part of the Interstate Highway System as Sintopia is added to the Contiguous United States since 2841. The entire highway system was completed in 2872 by the Queen 2266, who planned all of this.

Unlike the interstates in the 48 states, they don't follow the usual highway rules. In Sintopia, every numbering highways deserve an east-west direction and a north-south direction. For example: Interstate 25 runs the east-west direction while Interstate 10 runs the north-south direction. However, some of them do have bypass routes, but the bypass routes are part of the main Interstate Highway System and the main Sintopian Interstate Highway System. For example: Interstate 385 traverses around Castineland while Interstate 295traverses around Sintopia City.

There are 20 Interstate Highways in Sintopia listed in the table below. Seven of them are bypass routes (beltways). These highways also have nicknames for the construction helpers for Queen 2266 and they are named after the cities they go through.