The Internal Structure of Cities
Here we look at models that describe the internal structure of cities in more detail. Some terms to note are:
the
central business district (CBD), which is the easiest region of any city to recognise, as this is generally
the first part of the city to develop and remains as an industrial or administrative core of the city and is
often the city centre, if not geographically then in terms of transport it will be where the transport routes
converge and where the main train, subway and bus stations will be located. We shall look at how the
functions of the CBD continue to change later. Around the CBD there is often a
transition zone, in which a
mixture of industry and housing is located. Often industries that are either unable to afford expensive land
in the CBD site here, as do those services which gain little advantage from being in the CBD. For example,
specialist shops like jewellers and furniture stores may locate here, on the assumption that people will
make the effort to travel there for these special commodities. However, most people only pass through the
transition zone on their way to the CBD and businesses located here may go undetected by many potential
customers. Consequently, these places are often characterised by economic depression and
degeneration. The
suburbs are largely middle class houses on the periphery of the city.
Burgess’ Concentric Zone Model, 1925.

The diagram above shows Burgess's model of a city. Burgess followed the ecological school of thought
that saw cities rather like ecosystems in which
people compete for resources. (It has to be said that this
was the old Darwinian evolutionary way of thinking but in modern evolutionary theory, cooperation can be
at least as important as competition). This lead to a
demand-dominated model in which demand for better
housing drives the wealthiest away from the aging and decaying housing near the industrialising city
centre toward the periphery where new expensive housing is constructed to satisfy this demand. Similarly,
industry also competes for the most desirable land. This leads to
invasion of the best land by those
residents and industries that can afford it. Furthermore,
dominant land uses may take over large regions
of the city, for example the central business district (CBD) expands into the surrounding transition zone.
The result is that
natural areas develop in the city as a result of these ‘natural’ processes.

Combined with these facts Burgess also incorporated the effects of mass immigration and social class into
his model. Immigrants from poorer countries, or freedmen from the plantations, flocking to a rapidly
expanding city in search of work, would be forced to occupy the worst housing since they have the weaker
competitive position. Furthermore, ethnic immigrants tend to stick together as they form neighbourhoods
which speak their language and in which their culture dominates, for example Chinatowns. This results in
ethnic divide as well as social divide within cities. This racial and economy driven sorting of residential
households tends to create a series of concentric circular zones within the city, as shown in Burgess’
model below. The transition zone (zone 2) is a mixed industrial/residential area often comprising low
income residential areas or
slums, skid rows and ethnic ghettos. Zone 3 is the blue collar residential zone
or the ‘workingmen’s quarters’ and is more stable than zone 2 and is often ethnically dominated by those
who managed to break free from the ghettos and are moving toward the periphery as they demand better
housing and as the CBD pushes into the transition zone. Zone 4 is middle class housing where established
city residents dwell, many having moved outwards as the city grew and public transport developed. These
people commute to work in the CBD.

Burgess applied his model to Chicago, as shown in the diagram below:
Chicago was Burgess’ home town. The city core was destroyed in the Great Fire of 1871 and as the city was
rebuilt, more obvious social patterning evolved and Chicago became a segregated city with concentric zones.
Burgess’ model was either the source of his model or the first test of his model, or perhaps both (?).
Nevertheless, the model describes Chicago well, albeit in a simplified way, since the detailed housing patterns
do not exactly match the concentric zones, but the model is a good approximation.

Chicago was formally and legally ethnically segregated until the 1870s with schools, public transport, hotels and
restaurants enforcing racial segregation. School segregation officially ended in 1874. However, educational
and employment discrimination continued in practise. In the 1840s there were about one thousand African
Americans in Chicago, but that number soared to 15 000 by 1890 and 40 000 by 1910 and continued to rise.
By 1910, 78% of this ethnic group lived in the dilapidated housing along the
Black Belt (see diagram). These
people simply found it hard or impossible to find work as employers preferred not to employ them. This
discrimination lessened, temporarily,  by necessity during World War I when black people were needed in
industry. However, the problems encountered by this ethnic group did not end overnight! In 1919, 26 American
cities, including Chicago witnessed race riots.

During the 1920s, the black Americans, especially in Chicago made a major contribution to American (and
World) culture, and one which seems under-acknowledged – the
Age of Jazz. Chicago saw the development of
bright-light districts, such as the Stroll on South State Street. These areas were characterised by night-life,
where people of all races would gather at to hear Jazz performances.

In the 1930s came the
Great Depression. In 1939, 50% of black families were on government aid and 40% of
the relief rolls went to black people, clearly they were the worst hit. This time saw an increase in black activism,
with the  ‘Spend your money where you can work’ campaign, which referred to the fact that many businesses
were happy to take money from black customers whilst refusing to employ black people!
World War II saw an increase in new jobs in Chicago, coupled to the increasing use of mechanical cotton-
pickers in rural places, there was a big increase in immigrant job-seekers from the countryside, this was the
Second Great Migration.

In the 1990s there was a burst of racial incidences in the police force. New housing schemes sought to
demolish 51 high rise low-income housing blocks and replace them with mixed housing. Residential ethnic
segregation continues, with some areas comprising more than 90% black people in the so-called ‘Black
Metropolis’.

Today
gentrification schemes are occurring in the near west and south sides of Chicago. Gentrification is the
process whereby old deteriorated industrial or low-class housing areas are regenerated, for example, riverside
industrial units in disuse after the decline of heavy industry may be replaced with middle-class apartments,
shopping centres and leisure centres. The new mixed housing causes controversy, with officials claiming that
enough is being built to house all the former residents of the high rise blocks, 50 out of 53 of which have now
been demolished, however, others claim that the poorest have been simply forced out onto the streets. A
ghetto bus tour takes tourists around the remnants of the all but destroyed ghetto area.

The Chicago
Chinatown has some 68 000 Chinese residents in its main area. In the 1870s Chinese people
came here as ex-railroad workers avoiding discrimination in the western states, and as immigrants fleeing the
communist revolution in China in the 1950s-1960s. Chicago grew rapidly, with its population increasing more
than 20 times from 1860 to 1910.

Chicago now has a population of more than 3 million and is the third most populous city in the USA and its
metropolitan area has a population of over 9.5 million, making it the third largest metropolitan in the USA.
The principle structural regions of Burgess’ Chicago are:

1. Loop (CBD), the business centre and the region of greatest mobility. Hotels are located here and the
residents are primarily transients. This area empties at night and fills in the morning.
2. Transition zone: occupied by slums. This was the former suburbs of the old city and was taken over by
businesses expanding from the CBD. Apartments here are flats, furnished rooms and are deteriorated and
occupied primarily by childless people.
3. Workingmen’s homes: roomers (on the edge of the slums) where factory workers and shop workers with
families dwell and unsettled young people – the ‘respectable’ working class.
4. Zone of better residences: apartments, small families and delicatessen shops. Here the middle class
residents dwell and this area is served by local subsidiary shopping centres.
5. The commuter’s zone: duplex apartments (houses converted into double flats), single dwellings, house
owners and families.

Further out we can identify two more concentric zones: 6: the agricultural district and zone 7: the hinterland.
Also note the following on the diagram: Little Sicily, an area so-called for its Italian culture and cuisine, even
though Italians apparently did not make up the bulk of the population but merely a large proportion. Note also
the Vice district, protected by organised crime, and used for its for illegal gambling houses and brothels. Note
also the area dominated by the Chicago underworld – gang crime was rife in some parts of early Chicago.

Criticisms of Burgess’ Model

Parts or sectors of each concentric zone often exist, but they rarely link up to form a complete ring around the
city centre. However, intervening barriers, such as old industrial centres, may prevent completion of the arc.
Burgess was a sociologist and so gave most emphasis to social class and ethnic factors in determining
residential land use and not much emphasis to other land uses. No model is ever perfect since it is a
simplification and generalisation of reality. Nevertheless, Burgess’ model gives great insight into the structure of
North American cities, especially in the recent past, and explains some of the factors that determined the
structure of these cities. It is impossible to deny that social class and race were major factors in the growth of
many American cities – the ghettos were a reality, although some debate how much of the reality was media
hype at the time, nevertheless these places existed. Furthermore, race and social class continue to be major
issues in modern North American cities.

Hoyt’s Sector Model, 1939

Hoyt analysed 142 American cities and mapped the residential rents block by block and found that the spatial
arrangement was described better by using sectors rather than concentric circles (though indications of the
concentric regions still occur in Hoyt’s model). Initially a mix of land uses develops in the city centre and then,
as the city expands outwards, these extend along sectors. High rent neighbourhoods follow high ground, or
extend along non-industry river or lake fronts, or along communication lines or toward open country. Low
income people may occupy the old and deteriorating housing vacated by the wealthy as they moved on to
better areas (such houses are further divided into small apartments) or they occupy regions near to industry or
twilight zones and other undesirable areas. Old decaying housing remains in the centre as new expensive
housing is built on the periphery of the city, so some concentric zoning still occurs. Hoyt’s model is an extension
rather than a replacement of Burgess’ concentric zone model.

Hoyt’s model
emphasises supply rather than demand – construction of new housing allows the wealthy to
middle classes to move out to the periphery and their vacated housing can then be divided up into apartments
and rented to low income groups, a process known as
filtering.

Robson's Model, 1963-75: a modification of Burgess' and Hoyt's models.

One problem with Hoyt’s model is that it over-emphasises economic social class and ignores ethnic factors.
Although developed for American cities, Hoyt’s model has been applied, with some success, to the English city
of Sunderland by
Robson in 1963, as shown in the diagram below. The model had to be modified to take into
account unique physical factors, such as the coastal position and the River Wear running through the city and
it was found that a more or less equal emphasis on sectors and concentric zones best fitted Sunderland. Note
that this was applied to Sunderland as it was in 1963-1975 and note the dominance of heavy industry such as
shipbuilding and engineering and the dominance of low and medium income housing. This example illustrates
how models can apply well to specific cases, but typically require some modification. Another point to note, is
that in contrast to North American cities, in British cities there are often found large council housing estates on
the periphery of a city. This housing, though not middle-class is sometimes of near middle-class quality (though
sometimes it is low quality high rise flats).
Above: Hoyts' sector model.

Below: Hoyts' model applied (and modified) to Sunderland, England. Note: rooming houses occupied by
roomers are more often called lodging or boarding houses in England and are houses in which the
land-owner lets out one or more rooms.
Harris and Ullman's Multiple Nuclei City Model (1945)

This model does not assume that cities grow around a single CBD - although the CBD is retained additional
nuclei are recognised. For example, industry may locate near to transport routes, such as major roads, canals,
ports or railway lines. Some activities also repel one another, for example high-class housing locates far away
from industry. There are also businesses that would benefit from being sited in the CBD but cannot afford the
high cost of land there, especially if they require large areas of land, for example warehouses often locate in
transition zones or in suburbs. Finally, similar activities may group together, such as the Jewellery Quarter in
Birmingham, UK (why?). The multiple nuclei model is shown below:
The advantages of this model lie in its multinuclei approach - many sources give slight varaints on the model
shown in the diagram, since the model is rather flexible and adapts to local situations (the exact positions of the
nuclei are not important but only the basic trends) so it can be modified to match the city under consideration.

These concentric ring, sectorial and multiple nuclei models are the so-called classical models of urban land
use. Cities may in reality be a mixture of all three. For example, London has concentric rings, with older and
poorer inner city areas and more affluent suburbs. London also exhibits sectors, such as  the zone of worker's
dwellings that developed in the industrial revolution and extended from the East End to Dagenham and beyond.
An affluent residential sector developed in the north and west, from Mayfair to the Chiltern hills. London also
contains multiple nuclei, such as the financial centre or the centre of medical services around Harley Street
(similarly banks and media institutions tend to be clustered).

We have seen how these classical models, which were all based on North American cities in the first half of the
twentieth century can be applied with some success to cities in other places at other times, for example we saw
how Robson modified the Burgess and Hoyt models and applied them to Sunderland, England in the 60s and
70s. In particular, Burgess' model works well to cities that grew very rapidly, due to massive immigration - a
characteristic of many North American cities. Coming soon we shall look at other variants of these models as
applied to British cities. We shall then go on to look at models of cities in the less economically developed
world, such as cities in Asia and Africa.
Vance’s urban realms model is an extension of the multiple-nuclei model and is based on the San Francisco
Bay area but has been applied to other US cities. The key feature is the emergence of large self-sufficient
urban areas, each focused on a centre independent of the traditional downtown and central city. The area,
shape and other characteristics of each realm depends upon the following several factors:

1. The terrain – mountains and rivers and other barriers will help to determine the extent and shape of a region.

2. The size of the metropolis – a larger metropolis may have more and larger realms.

3. The amount of economic activity within each realm – a determinant of the area it can serve and hence its
size.

4. The transport infrastructure available within each realm – an easily accessible economic core increases the
area of influence and thus size of each realm.

5. Transport infrastructure between realms – e.g. circumferential links (such as freeways) and airports such
that people no longer have to travel to the CBD and its central realm in order to travel to other realms and to
other metropoli. If a realm can become more important in this manner then it may increase in importance. E.g.
West Los Angeles is within easy reach of the LAX airport (along the freeway) but to travel by train residents
have to travel to the CBD (by bus or car).
Burgess model
Burges Model Chicago
Hoyt's Sector Model
Hoyt's Model of Sunderland
Harris and Ullman's Model
Vance's Model
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