If you ever get stuck in traffic that is slower than walking speed — or if the traffic is at a dead stop altogether — you should know about alternate routes for interstate highways in the United States to help you get to your destination faster.
Alternate Routes For Interstate Highways in the United States
I was driving northbound on Interstate 65 in Alabama yesterday, Sunday, June 1, 2025 when I noticed just before I reached exit 151 that traffic ahead was at a complete standstill. Fortunately, I was able to immediately exit and take Alabama State Highway 97 south to United States Highway 31 north, as I knew that Highway 31 generally parallels Interstate 65 and intersects with it at exit 164.
The Interstate Highway System is also known as the Eisenhower Interstate System, as the administration of Dwight David Eisenhower developed a proposal for an interstate highway system after he officially became president of the United States in January of 1953, which eventually resulted in the enactment of the Federal-Aid Highway Act of 1956, which is also known as the National Interstate and Defense Highways Act of 1956.
Although many anomalies exist, interstate highways are organized by their numbers, as primary interstate highways — which have either one digit or two digits — with:
- Odd numbers go north and south.
- Even numbers go east and west.
Interstate highways with lower numbers are found in the western or southern United States; and each interstate highway gradually increases to where interstate highways with higher numbers are found in the eastern or northern United States — so Interstate 5 runs north and south in the western United States; while Interstate 90 runs east and west across the northern United States.
The federal United States highway system is organized the opposite way — meaning that United States highways with lower numbers are found in the eastern or northern United States; and each United States highway gradually increases to where United States highways with higher numbers are found in the western or southern United States — so United States Highway 1 runs north and south in the eastern United States; while United States Highway 70 runs east and west across much of the southern United States.
Auxiliary interstate highways with three digits are known as:
- Spur routes, which usually start with an odd digit and means the highway connects at only one end to the Interstate Highway System — typically with the primary interstate highway after which it was named. One of many examples is Interstate 190 in Illinois, which primarily connects traffic between Chicago O’Hare International Airport and Interstate 90.
- Circumferential routes, which usually start with an even digit and means the highway circles partially or completely around a city while connecting to at least one interstate highway — typically with the one of the primary interstate highways after which it was named. One of many examples is Interstate 285, which circles around Atlanta in a continuous loop and connects to Interstate 20, Interstate 75, and Interstate 85. Circumferential routes are also known as perimeters, beltways, or beltlines.
- Bypass routes, which usually start with an even digit and means the highway connects at both ends to the Interstate Highway System — typically with the one of the primary interstate highways after which it was named. One of many examples is Interstate 270 in Maryland, which connects traffic between Interstate 495 — which is also known as the Capital Beltway which circles around the District of Columbia — and Interstate 70.
Many interstate highways either parallel or share routes with the United States highways that preceded them. This is a list of interstate highways which United States highways generally parallel partially or completely, in case the interstate highway is severely impeded due to construction, an accident, or some other reason:
- Interstate 5 — United States Highway 101
- Interstate 10 — United States Highway 90
- Interstate 15 — United States Highway 89
- Interstate 16 — United States Highway 80
- Interstate 20 — United States Highways 78, 80, and 278
- Interstate 24 — United States Highway 41
- Interstate 25 — United States Highway 85
- Interstate 30 — United States Highway 67
- Interstate 35 — United States Highways 69 and 77
- Interstate 40 — United States Highway 70
- Interstate 49 — United States Highway 71
- Interstate 55 — United States Highway 61
- Interstate 59 — United States Highway 11
- Interstate 64 — United States Highway 60
- Interstate 65 — United States Highway 31
- Interstate 70 — United States Highway 24
- Interstate 75 — United States Highways 11, 25, 27, and 41
- Interstate 77 — United States Highway 21
- Interstate 78 — United States Highway 22
- Interstate 80 — United States Highways 6, 30, 46, and 322
- Interstate 81 — United States Highway 11
- Interstate 84 — United States Highway 6
- Interstate 85 — United States Highway 29
- Interstate 87 — United States Highway 9
- Interstate 90 — United States Highways 6, 12, and 20
- Interstate 91 — United States Highway 5
- Interstate 93 — United States Highway 3
- Interstate 94 — United States Highway 41
- Interstate 95 — United States Highways 1 and 301
Final Boarding Call
Interstate highways help millions of people travel across the United States expeditiously every day. I can discuss the highway systems and their anomalies in the United States — and even outside of the United States — all day long. Some of the articles I have written about interstate highways include:
- States Own Interstate Highways — Not the Federal Government — and Other Fun Facts
- Standing in the Middle of the Eastern End of Interstate 70
- Interstate 49: The Ultimate Boredom?
The aforementioned list is by no means perfect or complete; but it could very well be useful if you are ever caught in a seriously substantial backlog of traffic.
Please feel free to add your own suggestions in the Comments section below so that other readers of The Gate With Brian Cohen can benefit and potentially save a significant amount of time.
All photographs ©2017 and ©2020 by Brian Cohen.
