Settlements can be described as being part of the urban hierarchy. Where they stand on the hierarchy depends on a number of factors, the main ones being population, the number of services a settlement has and its sphere of influence. The best way to show the urban hierarchy is by using a pyramid, as shown in the diagram later.
The most obvious way of deciding where a settlement ranks on the urban hierarchy is by using the population of that settlement. The larger the population, the higher the settlement is placed on the hierarchy.
In the UK, the largest city in terms of population is London, which most people would agree is the most important settlement in the country and so deserves to be placed on the top of the urban hierarchy for the UK.
After that the divisions between what is classified in each layer is a bit more vague. Different sources will have different numbers for how many people are needed for a place to be called a city rather than a town for instance.
However the most important thing to notice on the diagram is that as you go up the hierarchy, there becomes a lot less of that type of settlement. So, the diagram shows us that there are huge numbers of isolated farmhouses and hamlets. There are less villages and small towns and so on.
In the UK, many people would argue that only London should be placed in the highest rung of the triangle. However some other large cities, such as Birmingham, Manchester and Leeds are growing fast, and may be considered to have reached the top level as well.
Services are things such as retailers(shops), professionals (doctors, lawyers etc), entertainment, government functions and leisure. The theory goes that the larger a settlement is, and therefore the higher it is on the urban hierarchy, the more services and functions it will have.
In general in the UK, this is the case. London is the settlement at the top of the urban hierarchy, and it has the greatest numbers of services and functions of any settlement in the country. For instance, it has the major international airports, it is the seat of our national government, it has the widest range of shops, including very specialist ones, and it has the most renowned professional services. This is because its population is large enough to support all of the services.
A small village may on the other hand only have the population to support a pub, post office, village store and perhaps a small garage.
Villages and other rural settlements have found over the last 20 years that it has been increasingly hard for services to remain viable in these settlements. Small post offices and banks have frequently been closed down, as there aresimply not enough people using them to make them viable.
The number of services (functions) that a town provides normally relatesto the number of people living there.
There are however, two noted anomalies. These are examples of settlements that do not conform to the general pattern, and they are explained below:
Anomaly A: A Tourist town: Towns, such as Brighton, Blackpool and Eastbourne, that have grown due to the tourist industry, often have more services than their population suggests they should have. This is because many of their services are catering for the huge numbers of tourists who flood into the towns during the summer months. Hotels, guesthouses, restaurants, beach shops and ice cream stalls all are aimed to provide services for the tourists.
The extra tourist numbers swell the total population during the summer to a level that is more appropriate for the number of services provided.
Anomaly B: A Commuter Settlement: Many rural villages are becoming commuter centres, where people live, but work elsewhere. Many villages and towns around the London area fulfil this function.
Commuter settlements have a large resident population, but as very few of them actually work in the village, there is nobody to support any services. The commuters will do their shopping and banking in the city where they work. This means that these settlements will have fewer services than their population suggests they should have. Some commuter settlements are changing their services to cater for the different residents, with restaurants and cafes replacing the traditional village services.
The sphere of influence of a settlement describes the area that is served by a settlement, for a particular function. Its sphere of influence for different functions may cover vastly different areas. For instance a supermarket may attract people from a 20-mile radius, whilst a leisure activity, such as going to the theatre may attract them from far further away.
The larger a settlement is the greater its sphere of influence is likely to be, as it has a wider range of services and functions to attract people to go there. This is shown in the diagram below. A small village may only have a village store selling the daily newspaper and food such as bread and milk. People will only travel the shortest distance they need to buy these products. They are described as being convenience goods. In other words, something that you can buy easily and for the same price all over the place.
A larger town would have a wider sphere of influence because it would have shops and services that are more specialist, and so people would be willing to travel further to use them. An example might be a furniture shop. This sells comparison goods, in other words products that you might shop around for before going ahead and buying something.
There are two major ideas to consider when looking at the sphere of influence of a shop of service. These are called the range and threshold population of a good.
The range of a good or service describes the maximum distance that someone would be willing to travel to obtain that good or service. A newspaper shop has a small range because people will not travel far to use them. A cinema has a much wider range as people are prepared to travel much further to go to it.
The threshold population of a good or service is the minimum number of people needed to allow that shop or service to be successful. The more specialist a shop is the larger its threshold population is.
A newsagent will have a small threshold, where as a supermarket like Tesco's needs a much larger population before it can consider opening a store.