4 ms·

> The city is optimized to make travel distances as long as possible. On the other hand, it's also optimized to reduce the number of dimensions of travel from

> The city is optimized to make travel distances as long as possible. On the other hand, it's also optimized to reduce the number of dimensions of travel from 2 to 1. You never have to transfer from an east-west train to a north-south train (or vice versa). Literally everything is on your route. Transfers add time to your trip because instead of waiting for a train, boarding, and deboarding once, you do all of that twice. Your trip time isn't just time riding on the train. It's all that other stuff, too. (You probably still do have some transfers with local and express trains. That's an issue in 2D rail systems, too, but it's probably worse in 1D because of increased travel distances.) Combined trips also become easier. If two destinations lie in the same direction from your starting point, then one of them is directly on the way to the other. I'm not saying it's necessarily a net win, but it's at least a trade-off.

blargey 4y ago
> You never have to transfer from an east-west train to a north-south train (or vice versa). Literally everything is on your route. You can accomplish that in 2D by making the train line a ring, like the Yamanote Line of Tokyo. That way you halve the max distance traveled, and can “cut across” on car, foot, bike, other-train, etc where the main train line would still be inefficient.
- adrianmonk 4y ago
  Yeah, that's an interesting idea. In fact my first thought was, why not make this a circle instead of a line? But they say it's going to have super high speed rail. From Wikipedia (https://en.wikipedia.org/wiki/The_Line%2C_Saudi_Arabia https://en.wikipedia.org/wiki/The_Line%2C_Saudi_Arabia): > The transportation layer will include a high-speed rail system, which is claimed to allow people to go from one side of the city to the other side in 20 minutes when finished, reaching a speed of 512 km/h, which is faster than existing high-speed rail at the time of announcement. Maybe they think a perfectly straight line makes that easier to build. Or maybe they just think their rail is so fast that distance becomes a minor issue. Future expansion is also interesting to think about. If you make it a line, you can expand by adding, say, 10% onto the end. Once you've built a circle, it's hard to make it 10% bigger. But I guess you could double a circle by adding another circle and turning it into a figure 8. The figure 8 would have similar advantages to a circle since they are both closed loops.
  - mc32 4y ago
    Heh, that reminds me of olden Chinese earthen doughnut fort dwellings: https://en.wikipedia.org/wiki/Fujian_tulou https://en.wikipedia.org/wiki/Fujian_tulou except in greater gigantic proportions (pun on the doughnut). Circle expansion: they could add interior and or exterior concentric circles or semi circles --but then that would complicate the simplicity, so maybe not.

blargey 4y ago

> You never have to transfer from an east-west train to a north-south train (or vice versa). Literally everything is on your route. You can accomplish that in 2D by making the train line a ring, like the Yamanote Line of Tokyo. That way you halve the max distance traveled, and can “cut across” on car, foot, bike, other-train, etc where the main train line would still be inefficient.

adrianmonk 4y ago
Yeah, that's an interesting idea. In fact my first thought was, why not make this a circle instead of a line? But they say it's going to have super high speed rail. From Wikipedia (https://en.wikipedia.org/wiki/The_Line%2C_Saudi_Arabia https://en.wikipedia.org/wiki/The_Line%2C_Saudi_Arabia): > The transportation layer will include a high-speed rail system, which is claimed to allow people to go from one side of the city to the other side in 20 minutes when finished, reaching a speed of 512 km/h, which is faster than existing high-speed rail at the time of announcement. Maybe they think a perfectly straight line makes that easier to build. Or maybe they just think their rail is so fast that distance becomes a minor issue. Future expansion is also interesting to think about. If you make it a line, you can expand by adding, say, 10% onto the end. Once you've built a circle, it's hard to make it 10% bigger. But I guess you could double a circle by adding another circle and turning it into a figure 8. The figure 8 would have similar advantages to a circle since they are both closed loops.
- mc32 4y ago
  Heh, that reminds me of olden Chinese earthen doughnut fort dwellings: https://en.wikipedia.org/wiki/Fujian_tulou https://en.wikipedia.org/wiki/Fujian_tulou except in greater gigantic proportions (pun on the doughnut). Circle expansion: they could add interior and or exterior concentric circles or semi circles --but then that would complicate the simplicity, so maybe not.