This is an interesting map to play around with. It allows you to see how many 15-minute neighborhoods and cities there are around the world. And it works by calculating the average time it takes to walk or bike to the closest 20 points of interest in 10,000 cities. These points include all of the usual suspects like places of work, schools, healthcare institutions, grocery stores, and so on. A blue cell indicates an average walk time < 15 minutes, and a red cell indicates an average walk time > 15 minutes. The darker the color, the shorter or longer the average time in minutes.

By this measure, it's hard to beat many/most European cities. Here are Paris and Barcelona:

The city propers are completely blue, and you have to go pretty far out (or up into mountains) to find areas that don't have 15-minute conveniences.

Toronto has a strong core and isn't terrible overall, but expectedly, we aren't as uniform and as deep blue as Paris and Barcelona:

Where things get really interesting, though, is when you look at cities like Dallas and Houston:

It's clear where these cities stand on walkability.

Last week the Prime Minister of the UK, Rishi Sunak, announced a number of initiatives designed to support drivers. The slogan is "slamming the brakes on anti-motorist measures" and you can find more information about it, over here.

Naturally this is sparking the usual debate about driving vs. all the other forms of mobility. But it also seems to be part of some sort of broader political strategy intended to distance his party from things like environmental sustainability, net zero targets, and 15-minute city design.

If you're looking for a way to process the above announcement, this recent FT article by John Burn-Murdoch is an excellent place to start. Firstly, the UK (outside of London) is generally poorly served by public transport. This is an important thing to know. By the below measure -- percentage of large cities that have trams, a metro, or urban light rail -- it is even worse than the US:

In fact, one way to think about and measure mobility in the UK is to think in terms of the following geographic categories: there's US cities, European cities (including London), and then there's the rest of the UK. In the case of US cities, they have very clearly optimized around road infrastructure. Meaning, the vast majority of people don't take transit to work, but the area (km2) you can cover by car (in 30 mins) is high.

Look at Houston and Dallas on the left side of this graph:

On the other hand, European cities (again, including London) have optimized in the opposite direction. A lot more people walk, cycle, and take transit to work. In the case of cities like London, Paris, Barcelona, Bilbao, Prague, and others, the number is greater than 60%! However, they're sucky places to drive, as I learned this past summer. The area you can cover by car within 30 mins, is relatively low (bottom right of the above graph).

The challenge for British cities (excluding London), is that they seem to be right in the middle (burgundy dots above). Poor public transport (low percentage of trips to work). And poor road infrastructure (limited area accessible by car within 30 mins). So it is perhaps no surprise that Sunak is honing in on this issue. London is not representative of Britain. And based on the above data, the majority of people living in British cities are almost certainly mobility frustrated.

Of course, to correct this issue you have two options. You can move toward the left (in the above chart) and optimize for road infrastructure. Or you can move to the right and optimize for public transport and other forms of mobility. Based on last week's announcement, Sunak has chosen the left.

Charts: FT

This data is from 2019, but I imagine that things would look pretty similar today and that it might even be a little more pronounced. The dataset from the above article looked at how many people have cars in a given area (a darker dot = fewer cars) and then plotted this against population density and income per capita.

Here's what that looks like for the regions of New York, Boston, Los Angeles, and Houston (data from 2013 to 2017):

What is fascinating about these charts is that they show two different correlations. In dense and transit-rich cities such as New York and Boston, car usage is most closely linked with population density and not with income. The dark dots form a horizontal line near the top.

However, in the case of Los Angeles and Houston, car usage is instead most closely linked with income and not with population density. The dark dots form a vertical line near the left -- the lowest income per capita.

So what does this tell us?

It tells us that if you design a city to broadly require a car, then you are likely to sort people based on those that can afford a lot of car and those that cannot. On the other hand, if you design a city around transit, then you are likely to instead create a place where both the rich and poor get around in similar ways.

There is also evidence that the latter is being increasingly viewed as more desirable. 2017 was the first year in the US where high-income young people (ages 26 to 33) drove less than low-income young people. Presumably these high-income people had choices, and so I tend to view this as a preference.

As a whole, this is surely a good thing for our cities. But now I think we need to be careful not to allow density and walkability to become the new luxury that only the rich can afford.