Source: Wikipedia, the free encyclopedia.

Taj Hotel in Mumbai, Hong Kong, the São Paulo Metro

A city is a

, sometimes benefiting different parties in the process, such as improving the efficiency of goods and service distribution.

Historically, city dwellers have been a small proportion of humanity overall, but following two centuries of unprecedented and rapid

global issues, such as sustainable development, climate change, and global health. Because of these major influences on global issues, the international community has prioritized investment in sustainable cities through Sustainable Development Goal 11. Due to the efficiency of transportation and the smaller land consumption, dense cities hold the potential to have a smaller ecological footprint per inhabitant than more sparsely populated areas.[6] Therefore, compact cities are often referred to as a crucial element in fighting climate change.[7] However, this concentration can also have significant negative consequences, such as forming urban heat islands, concentrating pollution
, and stressing water supplies and other resources.

Other important traits of cities besides population include the capital status and relative continued occupation of the city. For example, country capitals such as Beijing, Jakarta, Kuala Lumpur, London, Manila, Mexico City, Moscow, Nairobi, New Delhi, Paris, Rome, Athens, Seoul, Singapore, Tokyo, and Washington, D.C. reflect the identity and apex of their respective nations.[8] Some historic capitals, such as Kyoto, Yogyakarta, and Xi'an, maintain their reflection of cultural identity even without modern capital status. Religious holy sites offer another example of capital status within a religion, Jerusalem, Mecca, Varanasi, Ayodhya, Haridwar, and Prayagraj each holds significance.


Map of Piraeus, designed according to the Hippodameian
grid plan
Palitana represents the city's symbolic role of devotion to the Jain temples.[9]

A city can be distinguished from other human settlements by its relatively great size, but also by its functions and its


U.S. states using a minimum between 1,500 and 5,000 inhabitants.[13][14] Some jurisdictions set no such minima.[15] In the United Kingdom, city status is awarded by the Crown and then remains permanent. (Historically, the qualifying factor was the presence of a cathedral, resulting in some very small cities such as Wells, with a population of 12,000 as of 2018, and St Davids, with a population of 1,841 as of 2011.) According to the "functional definition", a city is not distinguished by size alone, but also by the role it plays within a larger political context. Cities serve as administrative, commercial, religious, and cultural hubs for their larger surrounding areas.[16][17]

The presence of a literate elite is often associated with cities because of the cultural diversities present in a city.

taxation (food and other necessities or means to trade for them) to support the government workers. (This arrangement contrasts with the more typically horizontal relationships in a tribe or village accomplishing common goals through informal agreements between neighbors, or the leadership of a chief.) The governments may be based on heredity, religion, military power, work systems such as canal-building, food distribution, land-ownership, agriculture, commerce, manufacturing, finance, or a combination of these. Societies that live in cities are often called civilizations

The degree of urbanization is a modern metric to help define what comprises a city: "a population of at least 50,000 inhabitants in contiguous dense grid cells (>1,500 inhabitants per square kilometer)".[20] This metric was "devised over years by the European Commission, OECD, World Bank and others, and endorsed in March [2021] by the United Nations ... largely for the purpose of international statistical comparison".[21]


The word city and the related civilization come from the Latin root civitas, originally meaning 'citizenship' or 'community member' and eventually coming to correspond with urbs, meaning 'city' in a more physical sense.[10] The Roman civitas was closely linked with the Greek polis—another common root appearing in English words such as metropolis.[22]


toponymic terminology, names of individual cities and towns are called astionyms (from Ancient Greek ἄστυ 'city or town' and ὄνομα 'name').[23]


Hillside housing and a cemetery in Kabul
, Afghanistan

Urban geography deals both with cities in their larger context and with their internal structure.[24] Cities are estimated to cover about 3% of the land surface of the Earth.[25]


Downtown Pittsburgh at the confluence of the Monongahela and Allegheny rivers, which flow into the Ohio River

Town siting has varied through history according to natural, technological, economic, and military contexts. Access to water has long been a major factor in city placement and growth, and despite exceptions enabled by the advent of rail transport in the nineteenth century, through the present most of the world's urban population lives near the coast or on a river.[26]

Urban areas as a rule cannot

mining towns which play a vital role in long-distance trade, are cities disconnected from the countryside which feeds them.[28] Thus, centrality within a productive region influences siting, as economic forces would, in theory, favor the creation of marketplaces in optimal mutually reachable locations.[29]


Kluuvi, a city centre in Helsinki
, Finland

The vast majority of cities have a central area containing buildings with special economic, political, and religious significance. Archaeologists refer to this area by the Greek term

city center or downtown, sometimes coincident with a central business district

Public space

Cities typically have

Urban green spaces are another component of public space that provides the benefit of mitigating the urban heat island effect, especially in cities that are in warmer climates. These spaces prevent carbon imbalances, extreme habitat losses, electricity and water consumption, and human health risks.[33]

Internal structure

The L'Enfant Plan for Washington, D.C. combines a utilitarian grid pattern with diagonal avenues and a symbolic focus on monumental architecture.[34]

The urban structure generally follows one or more basic patterns: geomorphic, radial, concentric, rectilinear, and curvilinear. The physical environment generally constrains the form in which a city is built. If located on a mountainside, urban structures may rely on terraces and winding roads. It may be adapted to its means of subsistence (e.g. agriculture or fishing). And it may be set up for optimal defense given the surrounding landscape.[35] Beyond these "geomorphic" features, cities can develop internal patterns, due to natural growth or to city planning.

In a radial structure, main roads converge on a central point. This form could evolve from successive growth over a long time, with concentric traces of

town walls and citadels marking older city boundaries. In more recent history, such forms were supplemented by ring roads moving traffic around the outskirts of a town. Dutch cities such as Amsterdam and Haarlem are structured as a central square surrounded by concentric canals marking every expansion. In cities such as Moscow
, this pattern is still clearly visible.

A system of rectilinear city streets and land plots, known as the

compass points.[36][16][37][38] The ancient Greek city of Priene exemplifies a grid plan with specialized districts used across the Hellenistic Mediterranean

Urban areas

Aerial view of the Gush Dan metropolitan area in Israel, showing the geometrically planned[39] city of Tel Aviv (upper left), Givatayim to the east, and some of Bat Yam to the south.[40]

The urban-type settlement extends far beyond the traditional boundaries of the city proper[41] in a form of development sometimes described critically as urban sprawl.[42] Decentralization and dispersal of city functions (commercial, industrial, residential, cultural, political) has transformed the very meaning of the term and has challenged geographers seeking to classify territories according to an urban-rural binary.[14]


third millennium BC, can be seen at present-day Tell el-Mukayyar in Iraq

The cities of Jericho, Aleppo, Faiyum, Yerevan, Athens, Damascus, and Argos are among those laying claim to the longest continual inhabitation.

Cities, characterized by population density, symbolic function, and urban planning, have existed for thousands of years.[44] In the conventional view, civilization and the city were both followed by the development of agriculture, which enabled the production of surplus food and thus a social division of labor (with concomitant social stratification) and trade.[45][46] Early cities often featured granaries, sometimes within a temple.[47] A minority viewpoint considers that cities may have arisen without agriculture, due to alternative means of subsistence (fishing),[48] to use as communal seasonal shelters,[49] to their value as bases for defensive and offensive military organization,[50][51] or to their inherent economic function.[52][53][54] Cities played a crucial role in the establishment of political power over an area, and ancient leaders such as Alexander the Great founded and created them with zeal.[55]

Ancient times

proto-cities known to archaeologists.[49][56] However, the Mesopotamian city of Uruk from the mid-fourth millennium BC (ancient Iraq) is considered by most archaeologists to be the first true city, innovating many characteristics for cities to follow, with its name attributed to the Uruk period.[57][58][59]

In the

third millennium BC, complex civilizations flourished in the river valleys of Mesopotamia, India,[60][61] China,[62] and Egypt. Excavations in these areas have found the ruins of cities geared variously towards trade, politics, or religion. Some had large, dense populations
, but others carried out urban activities in the realms of politics or religion without having large associated populations.

Among the early Old World cities,

The Ancient Egyptian cities known physically by archaeologists are not extensive.[16] They include (known by their Arab names) El Lahun, a workers' town associated with the pyramid of Senusret II, and the religious city Amarna built by Akhenaten and abandoned. These sites appear planned in a highly regimented and stratified fashion, with a minimalistic grid of rooms for the workers and increasingly more elaborate housing available for higher classes.[65]

In Mesopotamia, the civilization of

first millennium BC, encompassed numerous cities extending from Tyre, Cydon, and Byblos to Carthage and Cádiz

In the following centuries, independent city-states of Greece, especially Athens, developed the polis, an association of male landowning citizens who collectively constituted the city.[67] The agora, meaning "gathering place" or "assembly", was the center of the athletic, artistic, spiritual, and political life of the polis.[68] Rome was the first city that surpassed one million inhabitants. Under the authority of its empire, Rome transformed and founded many cities (Colonia), and with them brought its principles of urban architecture, design, and society.[69]

In the ancient

Andean civilizations, Mayan, Mississippians, and Pueblo peoples drew on these earlier urban traditions. Many of their ancient cities continue to be inhabited, including major metropolitan cities such as Mexico City, in the same location as Tenochtitlan; while ancient continuously inhabited Pueblos are near modern urban areas in New Mexico, such as Acoma Pueblo near the Albuquerque metropolitan area and Taos Pueblo near Taos; while others like Lima are located nearby ancient Peruvian sites such as Pachacamac

Jenné-Jeno, located in present-day Mali and dating to the third century BC, lacked monumental architecture and a distinctive elite social class—but nevertheless had specialized production and relations with a hinterland.[71] Pre-Arabic trade contacts probably existed between Jenné-Jeno and North Africa.[72] Other early urban centers in sub-Saharan Africa, dated to around 500 AD, include Awdaghust, Kumbi-Saleh the ancient capital of Ghana, and Maranda a center located on a trade route between Egypt and Gao.[73]

Middle Ages

A map of Haarlem in the Netherlands, created around 1550, shows the city completely surrounded by a city wall and defensive canal, with its square shape inspired by the shape of Jerusalem

In the

Eastern Roman Empire, was the largest and wealthiest city in Europe, with a population approaching 1 million.[75][76] The Ottoman Empire gradually gained control over many cities in the Mediterranean area, including Constantinople in 1453

In the

Imperial Estates governing the empire with the emperor through the Imperial Diet.[77]

By the 13th and 14th centuries, some cities become powerful states, taking surrounding areas under their control or establishing extensive maritime empires. In Italy,

, which enjoyed considerable autonomy in late medieval Japan.

In the first millennium AD, the Khmer capital of Angkor in Cambodia grew into the most extensive preindustrial settlement in the world by area,[79][80] covering over 1,000 km2 and possibly supporting up to one million people.[79][81]

Early modern

In the West, nation-states became the dominant unit of political organization following the Peace of Westphalia in the seventeenth century.[82][83] Western Europe's larger capitals (London and Paris) benefited from the growth of commerce following the emergence of an Atlantic trade. However, most towns remained small.

During the Spanish colonization of the Americas, the old Roman city concept was extensively used. Cities were founded in the middle of the newly conquered territories and were bound to several laws regarding administration, finances, and urbanism.

Industrial age


world empire and cities across the country grew in locations strategic for manufacturing.[84] In the United States from 1860 to 1910, the introduction of railroads
reduced transportation costs, and large manufacturing centers began to emerge, fueling migration from rural to city areas.

Some industrialized cities were confronted with health challenges associated with

Factories and slums emerged as regular features of the urban landscape.[85]

Post-industrial age

In the second half of the 20th century,

industrialization and become the world's leading manufacturer.[88][89]

Amidst these economic changes,

master-planned cities from scratch on greenfield


Graph showing urbanization from 1950 projected to 2050.[94]

industrial revolutions urban population began its unprecedented growth, both through migration and demographic expansion. In England, the proportion of the population living in cities jumped from 17% in 1801 to 72% in 1891.[97] In 1900, 15% of the world's population lived in cities.[98] The cultural appeal of cities also plays a role in attracting residents.[99]

Urbanization rapidly spread across Europe and the Americas and since the 1950s has taken hold in Asia and Africa as well. The Population Division of the United Nations Department of Economic and Social Affairs reported in 2014 that for the first time, more than half of the world population lives in cities.[100][b]

Global South"—but the difference continues to shrink because urbanization is happening faster in the latter group. Asia is home to by far the greatest absolute number of city-dwellers: over two billion and counting.[96] The UN predicts an additional 2.5 billion city dwellers (and 300 million fewer country dwellers) worldwide by 2050, with 90% of urban population expansion occurring in Asia and Africa.[100][109]

immigrants from near and far.[112] A deep gulf divides the rich and poor in these cities, with usually contain a super-wealthy elite living in gated communities and large masses of people living in substandard housing with inadequate infrastructure and otherwise poor conditions.[113]

Cities around the world have expanded physically as they grow in population, with increases in their surface extent, with the creation of high-rise buildings for residential and commercial use, and with development underground.[114][115]

Urbanization can create rapid demand for

water resources management, as formerly good sources of freshwater become overused and polluted, and the volume of sewage begins to exceed manageable levels.[116]


The city council of Tehran
meets in September 2015

in Italy).

The chief official of the city has the title of mayor. Whatever their true degree of political authority, the mayor typically acts as the figurehead or personification of their city.[119]

City governments have the authority to make

extraction, recreation, and the nature and use of buildings. Technologies, techniques, and laws governing these areas—developed in cities—have become ubiquitous in many areas.[121]
Municipal officials may be appointed from a higher level of government or elected locally.[122]

Municipal services

Cities typically provide

school systems; policing, through police departments; and firefighting, through fire departments; as well as the city's basic infrastructure. These are provided more or less routinely, in a more or less equal fashion.[123][124] Responsibility for administration usually falls on the city government, but some services may be operated by a higher level of government,[125] while others may be privately run.[126] Armies may assume responsibility for policing cities in states of domestic turmoil such as America's King assassination riots
of 1968.


The traditional basis for municipal finance is local property tax levied on real estate within the city. Local government can also collect revenue for services, or by leasing land that it owns.[127] However, financing municipal services, as well as urban renewal and other development projects, is a perennial problem, which cities address through appeals to higher governments, arrangements with the private sector, and techniques such as privatization (selling services into the private sector), corporatization (formation of quasi-private municipally-owned corporations), and financialization (packaging city assets into tradeable financial public contracts and other related rights). This situation has become acute in deindustrialized cities and in cases where businesses and wealthier citizens have moved outside of city limits and therefore beyond the reach of taxation.[128][129][130][131] Cities in search of ready cash increasingly resort to the municipal bond, essentially a loan with interest and a repayment date.[132] City governments have also begun to use tax increment financing, in which a development project is financed by loans based on future tax revenues which it is expected to yield.[131] Under these circumstances, creditors and consequently city governments place a high importance on city credit ratings.[133]


The Ripon Building, the headquarters of Greater Chennai Corporation in Chennai, is one of the oldest city governing corporations in Asia

real estate developers act as the city's de facto urban planners.[136]

The related concept of

development assistance.[137] The concepts of governance and good governance are especially invoked in emergent megacities, where international organizations consider existing governments inadequate for their large populations.[138]

Urban planning

La Plata in Argentina is based on a perfect square with 5196-meter sides, and was designed in the 1880s as the new capital of Buenos Aires Province.[139]

Urban planning, the application of forethought to city design, involves optimizing land use, transportation, utilities, and other basic systems, in order to achieve certain objectives. Urban planners and scholars have proposed overlapping theories as ideals for how plans should be formed. Planning tools, beyond the original design of the city itself, include public capital investment in infrastructure and land-use controls such as zoning. The continuous process of comprehensive planning involves identifying general objectives as well as collecting data to evaluate progress and inform future decisions.[140][141]

Government is legally the final authority on planning but in practice, the process involves both public and private elements. The legal principle of eminent domain is used by the government to divest citizens of their property in cases where its use is required for a project.[141] Planning often involves tradeoffs—decisions in which some stand to gain and some to lose—and thus is closely connected to the prevailing political situation.[142]

The history of urban planning dates to some of the earliest known cities, especially in the Indus Valley and Mesoamerican civilizations, which built their cities on grids and apparently zoned different areas for different purposes.[16][143] The effects of planning, ubiquitous in today's world, can be seen most clearly in the layout of planned communities, fully designed prior to construction, often with consideration for interlocking physical, economic, and cultural systems.


Social structure


Landless urban workers, contrasted with peasants and known as the proletariat, form a growing stratum of society in the age of urbanization. In Marxist doctrine, the proletariat will inevitably revolt against the bourgeoisie as their ranks swell with disenfranchised and disaffected people lacking all stake[clarification needed] in the status quo.[145] The global urban proletariat of today, however, generally lacks the status of factory workers which in the nineteenth century provided access to the means of production.[146]


Clusters of skyscrapers in Xinyi Planning District, the centre of commerce and finance of Taipei, the capital of Taiwan

Historically, cities rely on

As hubs of trade cities have long been home to retail commerce and consumption through the interface of shopping. In the 20th century, department stores using new techniques of advertising, public relations, decoration, and design, transformed urban shopping areas into fantasy worlds encouraging self-expression and escape through consumerism.[148][149]

In general, the density of cities expedites commerce and facilitates knowledge spillovers, helping people and firms exchange information and generate new ideas.[150][151] A thicker labor market allows for better skill matching between firms and individuals. Population density enables also sharing of common infrastructure and production facilities, however in very dense cities, increased crowding and waiting times may lead to some negative effects.[152]

Although manufacturing fueled the growth of cities, many now rely on a tertiary or service economy. The services in question range from tourism, hospitality, entertainment, housekeeping, and prostitution to grey-collar work in law, finance, and administration.[87][153]

According to a scientific model of cities by Professor Geoffrey West, with the doubling of a city's size, salaries per capita will generally increase by 15%.[154]

Culture and communications

Paris is one of the best-known cities in the world.[155]

Cities are typically hubs for

skyscrapers, providing thousands of offices or homes within a small footprint, and visible from miles away, have become iconic urban features.[156] Cultural elites tend to live in cities, bound together by shared cultural capital, and themselves play some role in governance.[157] By virtue of their status as centers of culture and literacy, cities can be described as the locus of civilization, human history, and social change.[158][159]

Density makes for effective mass communication and transmission of news, through heralds, printed proclamations, newspapers, and digital media. These communication networks, though still using cities as hubs, penetrate extensively into all populated areas. In the age of rapid communication and transportation, commentators have described urban culture as nearly ubiquitous[14][160][161] or as no longer meaningful.[162]

Today, a city's promotion of its cultural activities dovetails with

Elvis lovers visit Memphis to pay their respects at Graceland.[168] Place brands (which include place satisfaction and place loyalty) have great economic value (comparable to the value of commodity brands) because of their influence on the decision-making process of people thinking about doing business in—"purchasing" (the brand of)—a city.[166]

Bread and circuses among other forms of cultural appeal, attract and entertain the masses.[99][169] Sports also play a major role in city branding and local identity formation.[170] Cities go to considerable lengths in competing to host the Olympic Games, which bring global attention and tourism.[171] Paris, a city known for its cultural history, is the site of the next Olympics in the summer of 2024.[172]


The atomic bombing of Hiroshima on 6 August 1945 devastated the city and led to Imperial Japan's surrender and the end of World War II

Cities play a crucial strategic role in warfare due to their economic, demographic, symbolic, and political centrality. For the same reasons, they are targets in asymmetric warfare. Many cities throughout history were founded under military auspices, a great many have incorporated fortifications, and military principles continue to influence urban design.[173] Indeed, war may have served as the social rationale and economic basis for the very earliest cities.[50][51]

Powers engaged in geopolitical conflict have established fortified settlements as part of military strategies, as in the case of garrison towns, America's Strategic Hamlet Program during the Vietnam War, and Israeli settlements in Palestine.[174] While occupying the Philippines, the US Army ordered local people to concentrate in cities and towns, in order to isolate committed insurgents and battle freely against them in the countryside.[175][176]

During World War II, national governments on occasion declared certain cities open, effectively surrendering them to an advancing enemy in order to avoid damage and bloodshed. Urban warfare proved decisive, however, in the Battle of Stalingrad, where Soviet forces repulsed German occupiers, with extreme casualties and destruction. In an era of low-intensity conflict and rapid urbanization, cities have become sites of long-term conflict waged both by foreign occupiers and by local governments against insurgency.[146][177] Such warfare, known as counterinsurgency, involves techniques of surveillance and psychological warfare as well as close combat,[178] and functionally extends modern urban crime prevention, which already uses concepts such as defensible space.[179]

Although capture is the more common objective, warfare has in some cases spelled complete destruction for a city. Mesopotamian

tablets and ruins attest to such destruction,[180] as does the Latin motto Carthago delenda est.[181][182] Since the atomic bombings of Hiroshima and Nagasaki and throughout the Cold War, nuclear strategists continued to contemplate the use of "counter-value" targeting: crippling an enemy by annihilating its valuable cities, rather than aiming primarily at its military forces.[183][184]

Climate change