Amazing video explains how numbering of US highways isn’t random: “Always knew there was a logic”
The late 1930s saw the start of a vast government road-building project called Dwight D. Eisenhower System of Interstate and Defense Highways. The numbering of the US Highways is not completely random, contrary to popular belief. A trending Facebook post by Rich Evans explains the sensible numbers assigned to highways across the United States. Construction began after Congress authorized spending in 1952. In 1956, uniform construction standards were adopted, governing things like access, speeds, the number of lanes, lane widths, and shoulder widths, per How Stuff Works.
Evans wrote in his post, "I always knew there was a logic to it, but I never saw it explained so well until I stumbled upon this delightfully informative short video on how the US interstates are numbered." The YouTube video explains that highways with 2-digits run across the length of the entire country. Roads ending with the digit '0' run from east to west. Those ending with '5' run from North-South. Bypasses have three numbers and contain the last two digits of the interstates they bypass. How Stuff Works further states that for north-south routes, the lowest numbers are in the west, and for east-west routes, the lowest numbers are in the south.
Interstate interchanges, commonly known as exits, have a numbering system. States, who are in charge of numbering, choose between two specified methods. In one method, each interstate route's sequential numbering scheme begins at the most western or southern point, and interchanges are numbered sequentially. The second method is called the milepost system where interchanges are ranked according to the miles counted starting at the most western or southern point. Interchange #4 would be the interchange that occurs between mileposts 4 and 5, as an example.
hen an interstate passes through a big city, the city's beltways are assigned a three-digit number. The primary route number and an even-numbered prefix are used to identify these routes. Prefixes go up to prevent duplication within a state.
People were surprised to learn this systematic numbering of the highways in the US. A user commented on the post, "Wow, that is interesting. Have never seen a map like this. Makes sense!" Another wrote, "We were traveling from duty station to duty station in the 70's watching them get built." Several users thanked Evans for sharing this information that was unknown to people who drive on these highways every day.