Cities over 10 million

What are the largest cities - the ones over 10 million? Or over 5 million? How are these important to the remaining task?

The exact count of cities in a certain population range depends in part on how those cities are defined and measured. Wikipedia on the largest cities (here) notes the UN’s use of three different definitions - the city proper, the extent of the urban area, and the metropolitan area.

By most definitions, Tokyo appears to be the largest city in the world, at least as measured in 2018 (the latest data readily to hand). It then had 37 million people in its metropolitan area (widest definition), and 13 million in the city proper. Over 100 countries - or half the world - have populations of less than 10 million, so the city of Tokyo is itself larger than the majority of the world’s countries.

In all, the Wikipedia article cited above (based on UN cities data) lists 22 cities that are more than 10 million in size at their narrowest definition (city proper) and 33 more than 10 million at widest definition. There are 48 larger than 5 million in size (city proper) and 81 at widest.

This accounted, in 2018, for over 854 million people - nearly 1 out of 8 people on our planet (12%) are in one of these 81 cities. While exact figures aren’t readily available, this would definitely translate to well over a billion people—perhaps as much as 1.6 billion?—in the metropolitan areas surrounding these cities.

Reaching the cities, then, means reaching as much as 10 to 20% of the population of our planet. Further, there’s an obvious strategic importance in that people in the cities will have ties to nearby, more rural areas—and people in some global cities will have ties back to places they originated from (like Bangladeshis in London, for example).

There is a challenge in reaching cities—the agglomerations are less amenable to the ‘people group’ approach that has dominated much of our missiological thinking and conversation. Nevertheless, the numbers involved suggest that we must balance city-based strategies with people group-based strategies in some way.