Urban Hierarchies

Settlements can be grouped into something called the "urban hierarchy," which is like a ranking system. This ranking depends on a few important factors. The first one is the population of a settlement. The bigger the population, the higher up it is on the hierarchy.

Another factor is the number of services a settlement has. Services can be things like schools, hospitals, or shops. The more services a settlement has, the higher it goes on the hierarchy.

The last factor is the "sphere of influence" of a settlement. This means how far the influence of a settlement reaches. A larger settlement with more services will attract people from a wider area. So, the bigger the settlement, the greater its sphere of influence.

Now, when we talk about the sphere of influence of a shop or service, there are two important things to consider. These are called the "range" and "threshold population" of a good.

The range refers to how far people are willing to travel to access a particular shop or service. For example, if there's a really good bakery in a town, people might be willing to travel a long distance to buy their delicious cakes.

The threshold population, on the other hand, is the minimum number of people needed to support a shop or service. Some businesses need a certain number of customers to be successful. For instance, a big supermarket needs a larger population to make enough sales.

By understanding the urban hierarchy, the size of a settlement, and its sphere of influence, we can see how settlements and services are connected and how they influence each other.

Let's consider an example of an urban hierarchy using different settlements in the United Kingdom.

1. At the top of the hierarchy, we have a large city like London. It has a very high population, numerous services such as hospitals, universities, shopping centres, and a wide sphere of influence. People from all over the country and even from abroad are attracted to visit or live in London.

2. Moving down the hierarchy, we have a smaller city like Bath. Bath is located in southwest England and is known for its Roman-built baths, Georgian architecture, and rich history. It has a population that qualifies it as a city, but it is smaller in size compared to major cities like London or Manchester. 

Despite its smaller size, Bath is still an important cultural and tourist destination, attracting visitors from around the world. It has a significant population, but fewer services when compared to London. Bath still offers amenities like hospitals, universities, and a variety of shopping options. Its sphere of influence extends to surrounding towns and smaller settlements.

3. Next, we have a medium-sized town like Harrogate. It has a smaller population than the cities but still offers important services such as schools, a hospital, and various shops. Its sphere of influence reaches out to nearby villages and rural areas.

4. Further down the hierarchy, we come across a small town like Kendal in the Lake District. It has a smaller population of between 25,000 and 50,000 residents and offers basic services like schools, a small hospital or clinic, and a limited range of shops. Its sphere of influence primarily covers the immediate surrounding rural areas. A small town is typically 

5. Finally, we have a small village like Lavenham, in Suffolk. It has a very small population (1,722, 2011 census), only basic services like a primary school and maybe a small convenience store. Its sphere of influence is limited to the immediate village and nearby countryside.

In this example, the urban hierarchy goes from the large city with the highest population, most services, and widest sphere of influence, to smaller cities, towns, and eventually to a small village with the smallest population and limited services and sphere of influence.