Edexcel GCSE Geography B Topic 3 Challenges of an urbanising world: a complete overview of urbanisation and megacities

What Topic 3 actually demands

Challenges of an urbanising world is Section C of Paper 1. It moves from the global picture of urbanisation and megacities, through how cities change over time, to a depth study of life inside one fast-growing megacity. Edexcel B tests understanding of urban processes, the ability to read urban data, and a detailed, factual case study.

This guide walks through the section in specification order, then sets out the exam patterns Edexcel B repeats. Each topic has a matching dot-point page; this overview ties them together.

Global urbanisation and megacities

The section opens with global urbanisation: past and projected trends, how they vary between developed, emerging and developing regions, the pattern of megacities (over 10 million people) and urban primacy. It covers how economic change and migration drive city growth and decline, the difference between formal and informal urban economies, and how cities change over time (urbanisation, suburbanisation, de-industrialisation, counter-urbanisation, regeneration) with changing land use.

The key skill is reading urbanisation line graphs (and calculating rates of change) and satellite images of land use.

The megacity case study

The depth study is quality of life in one megacity in a developing or emerging country (for example Lagos): its location, context and structure, the reasons for rapid growth, the opportunities and challenges it creates, the contrasts in quality of life between wealthy and poor areas, and the top-down and bottom-up strategies that make it more sustainable.

Case-study questions reward named districts, facts and figures, not generic city points.

How this topic is examined

A typical Edexcel B profile for Topic 3:

• Multiple choice and short answer. Defining urbanisation and megacity, classifying processes, and reading maps and photographs.
• Data response. Reading urbanisation line graphs (with a rate-of-change calculation) and satellite images of land use.
• Case-study questions. Using named facts about the megacity's growth, opportunities, challenges and strategies.
• Extended 8-mark answers. Assessing opportunities versus challenges, or the success of sustainability strategies, with a balanced, evidenced judgement and SPaG marks at stake.

Check your knowledge

A mix of recall and applied questions covering Topic 3. Attempt them under timed conditions, then check against the solutions.

1. Define the term megacity. (1 mark)
2. Explain why cities in developing and emerging countries grow faster than those in developed countries. (4 marks)
3. Explain how accessibility and cost influence urban land use. (4 marks)
4. For a named megacity, explain the reasons for its rapid growth. (4 marks)
5. For a named megacity, explain one challenge caused by rapid growth. (3 marks)
6. Explain one advantage of a bottom-up strategy for improving a megacity. (3 marks)