City

Key people

• Jaime LernerBrazilian politician and architect (1937–2021)
• Carlos MorenoColombian-French researcher, scientist, professor
• Jaroslav MillerCzech historian and university educator
• Mikael Colville-AndersenDanish urban designer and expert on urban mobility and bicycle friendliness

Timeline

• 1600 BCFrom 1600 BC, Dhar Tichitt, in the south of present-day Mauritania, presented characteristics suggestive of an incipient form of urbanism.
• 800 BCThe second place to show urban characteristics in West Africa was Dia, in present-day Mali, from 800 BC.
• 1480By 1480, these cities, as far as still part of the empire, became part of the Imperial Estates governing the empire with the emperor through the Imperial Diet.
• 1950Urbanization rapidly spread across Europe and the Americas and since the 1950s has taken hold in Asia and Africa as well.
• 1960By the 1960s, however, traffic congestion began to appear in such films as The Fast Lady (1962) and Playtime (1967).

Read

• A Tale of Two CitiesCharles Dickens · 1800Book
• The Emerald City of OzL. Frank Baum · 1910Book
• The Magic CityEdith Nesbit · 1910Book
• City of BonesCassandra Clare · 2007Book

Listen

• City Journal AudioManhattan InstitutePodcast
• City ConfidentialA&E | PodcastOnePodcast
• Socrates in the CitySocrates in the CityPodcast
• City Arts & LecturesCity Arts & LecturesPodcast

Voices to follow

• Justin Hollander@justinhollander · XUrban planning and design scholar
• Marco te Brömmelstroet@fietsprofessor · XUrban mobility researcher
• Olalekan Jeyifous@ojeyifous · XNigerian artist (born 1977)
• Otto Saumarez Smith@OSaumarezSmith · XArchitectural and urban historian

By the numbers

• 8.2BWorld population — global, 2025 (World Bank)
• 57.8Urban (% of people) — global, 2025 (World Bank)

Debates

• Does gentrification ultimately benefit urban communities?One view: Gentrification brings investment, new businesses, and improved infrastructure, revitalizing neglected areas. · Another: It displaces long-term residents, erodes local culture, and increases housing unaffordability for original inhabitants.Open question
• Are 'smart cities' the best path for future urban development?One view: Smart city technologies enhance efficiency, sustainability, and public services through data-driven solutions. · Another: They raise concerns about privacy, surveillance, and digital divides, potentially benefiting corporations more than citizens.Open question

Glossary

• UrbanizationThe process of increasing population in cities and towns, leading to the growth of urban areas.
• GentrificationThe process of renovating and improving a district, leading to an influx of more affluent residents and businesses.
• Social CohesionThe bonds or sense of belonging that unite members of a community within a city.
• Public SpaceAreas within a city that are open and accessible to all citizens, such as parks, plazas, and streets.
• Urban SprawlThe uncontrolled expansion of urban areas into surrounding rural land, often characterized by low-density development.
• Informal EconomyEconomic activities within a city that are neither taxed nor monitored by a government and are not included in official economic statistics.

Careers

Roles this can lead toward

Student research

Published policy papers by One Young India delegates — every delegate leaves published under their own name.

• Bridging the Synaptic Gap: From Neuroplasticity to Cognitive RenewalAmay Kashyap Deka
• The Plasticity Paradox: Technology’s Impact on The Adolescent BrainNeeti Singh
• Electricity: The backbone of an integrated energy systemPalakshi Singh

Threads 4

Where this connects to other fields — and why it's worth knowing.

• Infectious Disease & Pandemics Health

  Here's a shock: until about 1900, big cities killed more people than they birthed. They were so crammed and disease-ridden that they only grew by constantly pulling in fresh newcomers from the countryside. The city was basically running on a nonstop transfusion of village blood.

• Migration & Refugees Global Risks

  A refugee camp called Dadaab was meant to be temporary. Thirty years later it has markets, neighborhoods, and kids who were born and grew up there, it's a city now. 'Emergency' shelters have a habit of quietly hardening into permanent towns, because nothing is more permanent than something everyone calls temporary.

• Homeostasis Health

  Double an animal's size and it needs only about 1.85 times the blood vessels, not double, because big bodies run more efficiently. Astonishingly, the same math holds for cities: double a city's population and its roads, pipes, and cables grow only about 1.85 times. A giant city is efficient in exactly the way a giant elephant is, both following one hidden rule of scale.

• Complexity & Emergence Science

  Double a city's size and you don't just get double the inventions, wages, and crime. You get about 2.15 times as much. Cities follow a strange math rule where bigger means more of everything per person, both the genius and the danger. Cramming people together somehow multiplies what they produce.