The Urban Explosion: Why Are Cities Growing So Fast?

In 1800, only about 3% of the world's people lived in cities. Today, that figure is over 56% — and it is rising every year. By 2050, experts predict that around 7 in every 10 people on Earth will be city-dwellers. Think about the city or town nearest to you. Has it grown in your lifetime? Has your family ever moved from a rural area to find work or school? Cities are pulling people in like magnets — but why? And what happens when they grow too fast?

Urbanisation is the process by which an increasing proportion of a country's population comes to live in urban areas — cities and towns — rather than in rural areas such as villages and farmland. It is measured as a percentage: if 60% of a country's people live in cities, its urbanisation rate is 60%. URBAN vs RURAL An urban area is a built-up place with a large, dense population — a city or large town. A rural area is the countryside, with a smaller, more spread-out population. Urbanisation happens when more people move into urban areas than move out of them, or when cities grow to absorb villages around them. CAUSES OF URBANISATION Urbanisation is driven by push factors (reasons people leave rural areas) and pull factors (reasons people are attracted to cities). Push factors include: poverty and lack of jobs in rural areas; unreliable farming caused by drought or soil exhaustion; fewer schools and hospitals in rural regions. Pull factors include: more jobs, especially in manufacturing and services; better access to healthcare and education; higher wages and more opportunities for social mobility (the chance to improve your standard of living). Natural increase — when births outnumber deaths within a city's existing population — also adds to urban growth. WHERE IS URBANISATION HAPPENING FASTEST? Urbanisation is not happening at the same speed everywhere. In high-income countries such as the UK, Germany, and Japan, most people already live in cities, so urbanisation is slow. The fastest growth is in low- and middle-income countries in Sub-Saharan Africa and South Asia. Lagos, Nigeria — already home to over 15 million people — is one of the fastest-growing cities in the world. Mumbai, India, and Dhaka, Bangladesh, are also expanding rapidly as millions move from rural areas seeking better lives. EFFECTS OF URBANISATION Urbanisation creates both opportunities and challenges. Opportunities: economic growth, innovation, better access to services, and poverty reduction when jobs are plentiful. Challenges: housing shortages leading to the growth of informal settlements (areas of makeshift housing, sometimes called slums or shanty towns, where people lack clean water, sanitation, and secure shelter); traffic congestion; air and water pollution; pressure on schools and hospitals; and growing inequality — the gap between rich and poor within the same city.