3 ms·
The system was engineered to incorporate both loops and spurs, and it's encoded in the numbering system: I think most folks know that 2-digit interstates with
by myself248 4y ago
The system was engineered to incorporate both loops and spurs, and it's encoded in the numbering system:
I think most folks know that 2-digit interstates with an even first digit are east-west, and with an odd first digit are north-south.
But 3-digit interstates exist too. An even first digit means it's a loop around a city (like I-475 around Flint), and an odd first digit means it's a spur into downtown. (I-375 into Detroit). These numbers can be reused, for instance there's another I-375 in Florida.
I think the argument here is that the _default_ should've been to loop around cities.
- pandaman 4y agoAccording to this article https://en.wikipedia.org/wiki/Interstate_Highway_System#Primary_(one-_and_two-digit)_Interstates https://en.wikipedia.org/wiki/Interstate_Highway_System#Prim... there is no encoding in separate digits, only the whole number being odd or even has meaning. E.g I-10, I-14, I-30, I-70, I-72 etc are east-west and I-25, I-45,I-65, I-83 etc are north-south.
- erik_seaberg 4y agoWeren’t a lot of those loops absorbed by later growth? Much like siting an airport, it’s hard to pick a route that will always remain outside a city without just going to the middle of nowhere. Wikipedia says I-280 was planned in 1955, and I think Silicon Valley was mostly still fruit orchards at the time. The silicon transistor would be invented one year later.
- bobthepanda 4y agoThe main thing favoring bypasses is that orchards aren‘t neighborhoods full of people, so you avoid the initial destruction and displacement. What happens after the fact isn‘t as important.