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The majority of the world's population now live in urban areas.

Global shift of megacities

Common Mistake

Confusing world cities with megacities

Do not assume a megacity is automatically a world city. Tokyo is both. Lagos is a megacity (over 15 million people) but is not yet considered a major world city because it lacks global financial and political dominance. Conversely, Zurich is a world city due to its global financial influence, but its population is well under 1 million.

3. How Urban Growth Rates Vary

The rate at which urban areas grow is highly uneven across the globe. We can split these trends cleanly by a country's level of economic development:

High-Income Countries (HICs)

  • Trend: Very slow urban growth, and in some areas, urban populations are plateauing or declining.
  • Why?: HICs underwent rapid urbanisation during the Industrial Revolution (18th and 19th centuries) as steam-powered factories drew millions from the countryside. Today, the vast majority of people in HICs already live in cities (often 80% or more).
  • Current Movement: Many HICs are experiencing counter-urbanisation, where people leave crowded cities to move to rural villages or smaller towns, commuting back using modern transport and digital technology.

Newly Emerging Economies (NEEs) and Low-Income Countries (LICs)

  • Trend: Exceptionally rapid urban growth.
  • Why?: These countries are undergoing their own economic transitions right now. People are moving from agricultural rural areas to manufacturing and service-dominated cities.
  • Drivers of Rapid Growth:
    1. Rural-to-urban migration: Driven by push factors (reasons to leave the countryside, e.g., crop failure, mechanisation of farming replacing jobs, lack of healthcare) and pull factors (reasons to move to the city, e.g., higher-paying jobs, better access to schools, medical facilities).
    2. Natural Increase: The majority of migrants moving to cities are young adults (aged 18–35) seeking work. When they settle in the city, they often have children. This results in high birth rates. At the same time, urban areas usually have better access to hospitals, which lowers death rates. Therefore, births greatly exceed deaths.
Key Idea

The dual engine of urbanisation

Urban growth in LICs and NEEs is not just caused by people moving from the countryside. It is heavily accelerated by natural increase—the excess of births over deaths among the young migrant population already living in the city.

Worked Example: Calculating Percentage Change in Urban Growth

In GCSE exams, you will often be given data tables or graphs showing urban population figures and asked to calculate mathematical changes, such as the percentage growth of an urban area over time. This tests your AO4 (geographical skills) capacity.

Example

Calculating the percentage growth of an urban area

Scenario: The population of Lagos, Nigeria (an NEE), grew from approximately 7.2 million in the year 2000 to approximately 14.8 million in the year 2021.

Calculate the percentage increase in the population of Lagos between 2000 and 2021. Show your working and round your answer to one decimal place.

  1. Calculate the absolute increase in population
    Subtract the original population (from the year 2000) from the new population (from 2021):
14.8 million−7.2 million=7.6 million 14.8\text{ million} - 7.2\text{ million} = 7.6\text{ million} 14.8 million−7.2 million=7.6 million
  1. Divide the increase by the original value
    Take the absolute increase (7.6 million7.6\text{ million}7.6 million) and divide it by the starting population in 2000 (7.2 million7.2\text{ million}7.2 million):
7.67.2≈1.05556 \frac{7.6}{7.2} \approx 1.05556 7.27.6​≈1.05556
  1. Convert to a percentage and round
    Multiply the result by 100 to get the percentage value, then round to one decimal place as requested:
1.05556×100=105.556%≈105.6% 1.05556 \times 100 = 105.556\% \approx 105.6\% 1.05556×100=105.556%≈105.6%

Final Answer: The population of Lagos grew by 105.6% between 2000 and 2021.

Exam technique

In the exam

  1. Compare, don't just list: If a question asks you to "compare the rate of urbanisation in HICs and LICs", use comparative language. Don't write two separate paragraphs. Instead, write: "While urban growth rates in HICs are very slow or plateauing, the rate of urbanisation in LICs remains rapid."
  2. Be specific with your factors: When explaining rural-to-urban migration, always classify your points clearly into push and pull factors. Do not mix them up.
  3. Use the definitions carefully: If asked to define a world city, do not focus on population. Focus on terms like global influence, hub of finance, and command centre of the global economy.
Self review

Check yourself

  • Can you explain why London is classified as a world city, whereas Dhaka is classified primarily as a megacity?
  • Why does natural increase play such a significant role in the growth of cities in LICs compared to HICs?
  • What is the difference between counter-urbanisation and urbanisation?
Recap questions

1 of 5

A country already has most of its population living in towns and cities, and some people are now moving to villages or small towns while commuting back to work. Which description fits best?

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Two-part figure showing the global shift of major cities toward Asia and Africa and comparing megacity with world city, with Tokyo shown as both Urbanisation is the increasing proportion of people living in towns and cities. Today, the fastest urban growth is happening in many low-income countries (LICs) and newly emerging economies (NEEs), especially in Asia and Africa.

A megacity usually has more than 10 million people, but a world city is defined by global influence in finance, politics, and decision-making. Tokyo is both, Lagos is mainly a megacity, and Zurich is a world city without being a megacity.

Geographers are often asked to measure urban change from data. A common skill is percentage increase:

Percentage increase=new−originaloriginal×100 \text{Percentage increase} = \frac{\text{new} - \text{original}}{\text{original}} \times 100 Percentage increase=originalnew−original​×100

If both population figures use the same unit, such as millions, that unit cancels when you divide.

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What is the urban growth trend in HICs today?

Global urbanisation Revision Guide

  1. GCSE
  2. /Geography
  3. /Global urbanisation