| 1. | 0xdb8f...bcfd | 4.5M |
| 2. | jcandqc | 4.1M |
| 3. | baldinini | 941K |
| 4. | partytime | 939K |
| 5. | jimmyyyy | 918.6K |
| 6. | witcher01 | 898.8K |
| 7. | kualta.eth | 869.1K |
| 8. | Brandon Donnelly | 702.4K |
| 9. | ZORG | 487.3K |
| 10. | Ev Tchebotarev | 170.5K |
The other day I was speaking to a Korean friend of mine and he was telling me about Seoul's new GTX-A commuter railway line. This line opened at the end of 2024 and is part of a broader Great Train eXpress initiative that includes 3 lines (A, B, and C) and that is intended to establish a new "30-minute commute zone" surrounding Seoul. A is the first line to open. C is scheduled for completion in 2030. And already, three more lines are now being planned: D, E, and F.
What this first line has accomplished is pretty extraordinary. GTX-A connects Paju in the north to Seoul in the south. Paju sits at the northern border of South Korea (and therefore houses many US and South Korean Army bases) and has a population of over half a million people. Prior to GTX-A opening, this commute used to take approximately 90 minutes by conventional subway and up to 90 minutes by car, depending on traffic.
Today it takes exactly 22 minutes! If you're interested in seeing a complete walking video of this commute, click here.
The GTX system is a higher-speed railway line. Meaning, the trains are designed to operate up to a maximum speed of 180 km/h. Average speeds vary depending on the segment and stop spacing, but it seems to operate at an average speed of around 100 km/h. Paju to Seoul, for example, is around 33 km. So at 22 minutes, that's a blended average of 90 km/h. This means that there's no faster way to travel between these two points.
What this also means is that, as new GTX lines continue to come online, the geography of the Seoul urban region will continue to get redrawn. Suburban regions that were previously far out, are now going to get "pulled in" and function as more integral parts of a contiguous city. This improved access should also alleviate housing pressures by effectively opening up more supply.
I mean, 22 minutes is nothing. It can take longer than this to travel 3 blocks on a Toronto streetcar during rush hour. GTX is a prime example of the magic of rail and what's possible once you accept that highways (and tunnels underneath them) aren't going to be what efficiently move the most number of people around a big global city.
Cover photo by Ethan Brooke on Unsplash

Every five years, the Greater Golden Horseshoe Area (of southern Ontario) conducts something called a Transportation Tomorrow Survey. And I am told that it is the most comprehensive travel survey conducted anywhere in the world. So let's look at some of the data. The last survey was completed in 2022 and a mapping of the data was prepared by the School of Cities at the University of Toronto.
Population density:


Urban sprawl is how much of the US provides new housing. And here's Conor Dougherty in the New York Times arguing that America needs more of it to fix its housing shortage:
Even if all the regulatory restraints were removed tomorrow, developers couldn’t find enough land to satisfy America’s housing needs inside established areas. Consequently, much of the nation’s housing growth has moved to states in the South and Southwest, where a surplus of open land and willingness to sprawl has turned the Sun Belt into a kind of national sponge that sops up housing demand from higher-cost cities. The largest metro areas there have about 20 percent of the nation’s population, but over the past five years they have built 42 percent of the nation’s new single-family homes, according to a recent report by Cullum Clark, an economist at the George W. Bush Institute, a research center in Dallas.
The obvious benefit is that the resulting housing tends to be cheap. The above article is filled with examples of people buying large homes for a few hundred thousand dollars in newly formed communities across Texas. And if you live in a high-cost city, the social algorithms have almost certainly found you at some point with a shockingly cheap house in one of these places. But, Dougherty also admits that sometimes this may be the only redeeming quality:
Escobar told me he moved to Princeton because he could find a big house there for less than $300,000, but now the city is home, and he didn’t like where it was headed. Over the next four years, he said, his goal is to redevelop the downtown, try to attract offices where locals can work and build out a park system that voters recently funded with a bond measure. “You ask anybody what they love about Princeton, and it’s simply just the affordability,” Escobar told me. “We need to be more than that.”
According to the article, this isn't necessarily a problem, because it's just how cities are built in this day and age. What you do is start with low-cost housing in fringe locations. You grow as quickly as possible until traffic becomes "godawful" and vital infrastructure can't keep up. Then you implement moratoriums on new housing, and start working on other uses like, you know, employment. Eventually, after all this chaos is complete, you end up with something that possibly resembles a real city.
Percentage of trips by walking:

Percentage of trips by bicycle:

Percentage of trips by public transit:

Percentage of trips by car:

Percentage of residents with a driver's license:

Percentage of households without a car:

Average trips by distance:

Once again, these maps remind us that the starkest contrast is between active and non-active forms of mobility. In other words, we have a central core where many, and sometimes most people (>50%) walk to where they need to go, and then there's absolutely everywhere else in the region where most people drive (>50%) and, in some cases, where people drive almost exclusively (>90%). Public transit ridership is more dispersed, but it's really only dominant in Toronto, and not in any of the suburbs.
Perhaps the only reasonably uniform finding is that average trip distances tend to be relatively short (<10 km) no matter where you live.
Maps from the School of Cities at the University of Toronto; cover photo by Juan Rojas on Unsplash
Cover photo by Leon Hitchens on Unsplash
Share Dialog
Share Dialog
Share Dialog