Next time you're cruising on the interstate, take some time to spot all the different highway shields. Are there single digits? Double? Triple, even? What do the odd and even numbers actually mean? Believe it or not, there's a legit method behind the madness that makes up the United States interstate highway system and how they get their numbers.
- Interstate numbers ending in zero always travel east/west or coast to coast
- Interstate numbers ending in five always travel north/south or border to border
- Interstates with 2 digits traverse the entire country
- Interstates with 3 digits are bypasses and contain the last 2 digits of the interstates they bypass
- I-90 is the longest interstate in the country where you can drive continuously from Boston to Seattle
- America’s smallest interstate is 878 in New York which runs under a mile
- Hawaii, Alaska and Puerto Rico use their own interstate system as they are not connected to the rest of the country
