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Government, trade, industry, tourism and learning: what real cities do for the places around them, and why people travel farther for rarer services.
Paper packet. Every task here also exists on screen, where it is checked automatically; answers written on paper are not assessed by Nydus. When you are back at a device, enter your answers there.
You will name a city's functions, explain why people travel farther for rarer services, and show why a city is more than its population.
You know that settlements grow from hamlets to villages, towns and cities, and that bigger ones have more services. This lesson asks what those services are for, and who comes to use them.
| Term | What it means |
|---|---|
| Function | A job a city does, such as government, trade, industry, tourism or education. |
| Service | Something provided for people, such as a school, a store or a hospital. |
| Sphere of influence | The area whose people come to a city to use its services. |
| Commuter | A person who travels into a city to work or study and home again. |
| Capital | The city where a country's or state's government works. |
| Port | A city with a harbor where ships load and unload goods. |
A city is a crowd of people, but its real importance is what it does. Washington, D.C., governs the country. Houston's port sends oil and cargo around the world. Detroit built so many cars that it is called the Motor City. Orlando welcomes millions of visitors to its theme parks, and Boston is famous for its universities and hospitals. Most big cities do several of these jobs at once.
Because cities have services that villages and small towns do not, people travel in to use them. How far they travel depends on how rare the service is. Bread is needed daily and every town can have a bakery, so nobody travels far for it. A big hospital with specialist doctors is rare and costly, so a whole region shares one, and people travel a long way. The rarer the service, the bigger the area a city serves.
Another way: diagram
The dark squares are the city. Each dashed circle shows how far people travel to it for one kind of service: the smallest for something everyday, the biggest for something rare. The dots are villages, and the biggest circle takes in nearly all of them.
Another way: steps
To describe what a city does: 1. List the big employers: a port, factories, government, a university, hotels. 2. Ask who uses each: only the people who live there, or people from far away? 3. The functions that draw people from far away are the ones that make the city important to a whole region or country.
| City | People, about | Best known for |
|---|---|---|
| New York City | about 8 million | business, finance, trade |
| Albany | about 100,000 | government: New York State's capital |
| Long Beach | about 450,000 | one of the country's busiest ports |
| Hershey, Pennsylvania | about 15,000 | making chocolate, and tourism |
Albany is small and is the capital. Hershey is smaller still and is known all over the country. A city matters because of what it does and who comes to it, not only because of how many people sleep there.
Capitals exist to govern. Washington, D.C., holds Congress, the White House and the Supreme Court; every state has a capital where its legislature meets.
Many capitals are not their state's largest city. Sacramento, Springfield, Albany and Tallahassee were chosen for their central location or as compromises between bigger rivals, and they are capitals because of that function.
Port cities handle goods for whole regions. Ships unload containers at Los Angeles and Long Beach, oil and chemicals at Houston, and grain at New Orleans, and trains and trucks carry the goods on across the country.
A port serves places hundreds or thousands of miles away. The phone or shoes in a store in Chicago may well have come off a ship in California.
Some cities are known for making things. Detroit's car factories, Pittsburgh's steel mills and Seattle's airplane plants drew workers from far away and supplied goods to the whole world.
Industrial functions can change. Pittsburgh's mills closed, and the city now leans on hospitals, universities and technology, which shows that a city's functions are not fixed forever.
Some cities serve visitors. Orlando's theme parks, Las Vegas's hotels and the national parks' gateway towns exist largely to host people from elsewhere.
Others serve learners. College towns such as Ann Arbor, Michigan, and Chapel Hill, North Carolina, draw students from across the country and the world, and their populations swell every fall when classes begin.
A service needs enough customers to stay open. A corner store needs only a few hundred nearby, so there are corner stores everywhere. A children's hospital or a major airport needs millions, so there are only a few, and people travel far to reach them.
That is why the rarer the service, the bigger the circle of people it draws, and why big cities, with the rarest services, serve the widest areas.
Many people who work or study in a city live outside it. Every weekday morning they pour in by car, bus and train, and every evening they leave.
So a busy city holds far more people by day than by night. Washington, D.C., gains hundreds of thousands of commuters on a workday, a sign of how much it does for the region around it.
Checking an answer. People who leave for the day make a city emptier, so they are subtracted. A city that serves its region has more people by day than by night.
A function is defined by what a place does for people, so listing the city's big employers and who they serve describes its functions directly.
Counting the daytime population by adding and subtracting commuters is allowed because each person is in exactly one place at a time: those who come in are added to the city, and those who go out are taken away.
A city's sphere of influence is the area whose people come to use its services. A small town's sphere may reach only the farms around it; a big city's may cover several states.
Newspapers, TV stations and sports teams show a city's sphere clearly. Fans of the Denver Broncos come from across Colorado, Wyoming and beyond, because Denver is the largest city for hundreds of miles in every direction.
The relationship runs both ways. Cities need food from farms, water from distant rivers and workers from the suburbs and towns around them.
The towns and villages, in turn, need the city's hospitals, airports, universities and jobs. Understanding a city means understanding the whole area it is tied to, not just the people inside its limits.
The most common slip is judging a city only by its population. Another is thinking a capital must be the biggest city, when many capitals are smaller.
A third is thinking a city serves only the people who live in it. A fourth is adding the people who commute out instead of subtracting them when working out a daytime population.
Washington, D.C., was created for one function. In 1790 Congress passed the Residence Act, which placed the new national capital on the Potomac River, a compromise between northern and southern states. George Washington chose the site, and the government moved there in 1800.
The city was planned around its job. Pierre L'Enfant's plan placed the Capitol and the President's House at key points, joined by wide avenues. Today federal agencies, embassies, museums and the many businesses that work with the government fill the city.
Its sphere of influence covers the whole country and reaches around the world. On a workday, commuters from Maryland and Virginia swell its population far beyond the people who live inside its boundaries. Few cities show more clearly that a place matters for what it does, not how many people sleep there.
Side by side on the southern California coast, the ports of Los Angeles and Long Beach form the busiest container port complex in the United States. Huge ships from China, Japan, Korea and Vietnam unload millions of containers there every year.
Most of the goods do not stay in California. Trains and trucks carry them to warehouses and stores across the country, so shoppers in Texas, Illinois and Ohio depend on the two ports without ever seeing them. The ports and the businesses around them employ many thousands of people from towns all over the Los Angeles area.
When the ports slow down, the whole country notices. During the backups of 2021, dozens of ships waited offshore and store shelves across the nation ran short of some goods. A port's function reaches far beyond its city's edges, which is exactly what makes it important.
A city is defined only by its population. Albany is much smaller than New York City and is the capital; Hershey is small and famous. Ask what a city does.
A capital is always the biggest city. Albany, Sacramento and Springfield are all smaller than other cities in their states.
A city only serves the people who live in it. Every morning people pour in from the towns around it, and by day a busy city holds far more people than sleep there at night.
A family in a village buys bread at the village store. Name the kind of service.
$\text{everyday}$
The nearest place.
They drive to the market town for their big weekly shop. Name the kind.
$\text{less common}$
A bigger place.
Their grandmother needs an operation at the city hospital. Name the kind.
$\text{rare}$
The biggest place.
State the rule.
$\text{rarer service, longer trip}$
The sphere grows with rarity.
Ships from Asia unload at its port. Name the function.
$\text{trade}$
A port city.
Goods go on by rail and truck. Say whom it serves.
$\text{cities across the country}$
Far beyond itself.
Thousands from nearby towns work there. Name the effect.
$\text{jobs for its region}$
People come in to work.
Compare with its size.
$\text{about 450,000 people}$
Its reach is far larger.
State the conclusion.
$\text{a city matters for what it does}$
Not only for its size.
A city has $300$ thousand residents. Record them.
$300$
Thousand people at night.
$120$ thousand people commute in. Add them.
$300 + 120 = 420$
Fuller by day.
$30$ thousand residents commute out. Take them away.
$420 - 30 = 390$
The daytime population.
Find the net gain.
$120 - 30 = 90$
Thousand more by day.
Turn it into a percent of residents.
$\dfrac{90}{300} \times 100 = 30\%$
Nearly a third more.
Say what the gain shows.
$\text{the city serves its region}$
People come for its jobs and services.
Name what is there.
$\text{Congress, the White House, the courts}$
The national government.
Say whom it serves.
Name its main function.
Every city does many things, but some are best known for one. Match each real American city to the function it is best known for.
| making cars | running the country's government | welcoming tourists | a huge port for ships | |
|---|---|---|---|---|
| Washington, D.C. | ||||
| Houston, Texas | ||||
| Detroit, Michigan | ||||
| Orlando, Florida |
Complete the worked solution: a city has $500$ thousand residents. On a weekday $300$ thousand people commute in from the towns around it, and $100$ thousand residents commute out. Find the daytime population, the net gain, and the gain as a percent of the residents.
Add the incomers and take away the leavers.
$\text{residents} + \text{in} - \text{out} =$ d
Thousands of people by day.
Find the net gain.
$\text{in} - \text{out} =$ g
How much fuller it is.
Turn the gain into a percent.
$\dfrac{\text{gain}}{\text{residents}} \times \text{a hundred} =$ p
Compared with the people who live there.
Say what the gain shows.
$\text{the city serves its region}$
People come for its jobs and services.
Put these services in order, from the one people usually travel the **shortest** distance to reach, to the one they travel farthest for.
Number the steps in order (write the number in the box):
New York City has about 8 million people and Albany about 100,000, yet Albany is the capital of New York State. How can that be?
The three dashed circles show how far people travel to this city for three different services: fresh bread from a bakery, a high school, and a big hospital with specialist doctors. Each circle has a small diamond on it. Click the diamond on the circle for the **big hospital**.
This task has no paper form; do it on a device.
Two villages, Oak Grove and Birch Creek, are near a market town, and the town is near a city. The villages have no big stores and no hospital. The town has a big supermarket but no hospital. Only the city has a hospital. Draw where people from each place go for their **weekly shopping** and for a **hospital**. (People in the town and the city shop where they live.)
This task has no paper form; do it on a device.
A big city does many jobs at once. For each worker, name the city function they are part of.
| City function | |
|---|---|
| a crane driver unloading containers from ships | |
| a worker on a car assembly line | |
| someone writing new rules in a government agency | |
| a receptionist in a hotel near famous sights | |
| a professor at a university |
A city has $104$ thousand people living in it. On a weekday, $49$ thousand people travel in from the towns around it to work, study and shop, and $17$ thousand of its own people travel out. How many thousand people are in the city during the day?
Answer:
Here is a short report on Long Beach, California. Select **every** sentence that describes something the city *does* for people and places beyond it.
This task has no paper form; do it on a device.
Lesson test: one question per skill, one attempt each, no hints. Your answers are checked when you submit.
A city has $398$ thousand people living in it. On a weekday, $99$ thousand people travel in from the towns around it to work, study and shop, and $16$ thousand of its own people travel out. How many thousand people are in the city during the day?
Answer:
You can say what a city does. Tell somebody why Albany is New York's capital although New York City is far bigger. Next: the goods and people that move between places, and the routes they take.
23. Your turn: Washington, D.C., step 2
$\text{the whole country}$
Decisions for everyone.
23. Your turn: Washington, D.C., step 3
$\text{government}$
Whatever its size.