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North is a direction on the ground, not the top of the paper — and the arrow is how a map says which.
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 find a map's north arrow, work out where the other three directions are on that page, and use them on a map that is not printed north-up.
You can already name the four directions in order and give the opposite of any of them. You can also read a clock face. That is all you need here, because the compass never changes. What changes is which way around the paper is holding it.
| Term | What it means |
|---|---|
| North arrow | The mark on a map that says which way north is on that sheet. |
| Orient | To turn a map until its north arrow points the way real north is. |
| Page | The paper the map is printed on. |
| Ground | The real place the map shows; directions belong to it. |
| Quarter turn | One fourth of the way around, like three hours on a clock. |
Every proper map has a small north arrow printed somewhere on it. It does one job: it says which way north is on this sheet of paper.
Most maps are printed with north up the page, and that is a habit, not a law. A "You are here" map in a mall is printed to match the way you are standing in front of it. A map folded into a book may open sideways. A chart on a boat is turned to match the way the boat is going.
So: find the arrow, see which way it points, and then turn the other three directions around to match. They keep their order, north, east, south, west, clockwise, and the whole compass turns together.
On the island map in this lesson the arrow points at the right-hand edge. So north is right, east is down the page, south is left and west is up.
Another way: story
Hold a compass drawing on a sheet of paper and turn the paper. The four words go around with it. Nothing about the paper decides which way north is; the arrow does, and the paper just happens to be holding it.
Another way: diagram
Draw a cross with north at the top, then turn your page a quarter turn to the right. North is now pointing at the right-hand edge of your desk, and so is the island map's north.
Wherever the arrow points, the other three directions follow in order.
| North arrow points | East is | South is | West is |
|---|---|---|---|
| up the page | the right | down the page | the left |
| the right | down the page | the left | up the page |
| down the page | the left | up the page | the right |
| the left | up the page | the right | down the page |
Only the first row is the usual map. The other three are just as correct, and the arrow is how you tell which row you are on.
Picture a clock face drawn over the map, and think of the north arrow as one of its hands. A quarter turn clockwise is three hours. So wherever north points, east points three hours later, south six hours later and west nine hours later.
If the arrow points at the three, east points at the six, south at the nine and west at the twelve. After twelve, a clock starts again at one, so counting on from nine by three hours lands on twelve, and from twelve lands on three.
A map on a wall is most useful when it is turned to match the ground in front of it. If you stand facing a mall directory and the stores ahead of you are drawn up the page, you can walk "up" the map by walking forward.
So such maps are often printed with whatever is in front of you at the top, and that is not always north. The arrow, or a note on the map, tells you which way north really is.
Hikers orient a paper map: they turn it until its north arrow points toward real north, found with a compass or the sun. Then a trail that goes to the left on the map goes to the left on the ground, too.
Once a map is oriented, you can read it by looking: the lake drawn ahead of you is ahead of you. That only works if the arrow has been read and trusted.
Many phone and car maps can be set in two ways. North up keeps north at the top of the screen all the time. Heading up turns the map as you turn, so the way you are going is always the top of the screen.
In heading-up mode, north moves around the screen as the car turns corners. The screen shows a small arrow or the letter N so that you can still tell which way north is.
Checking an answer. North and south must be on opposite sides of the page, and so must east and west. If two directions share a side, something has slipped.
Reading the arrow first is allowed, and needed, because the arrow is the mapmaker telling you where north is on this sheet. Turning the other directions with it is allowed because the four directions are fixed to each other on the ground; turning the paper cannot change their order.
Counting three hours per quarter turn is allowed because a clock face goes around the same way, and four quarter turns of three hours make the twelve hours of a whole turn.
The most common slip is assuming north is up the page without looking for the arrow. Another is turning only north and leaving east on the right.
A third is mixing up the north arrow and the scale bar, which also sits in a corner of the map. A fourth is turning counterclockwise, which swaps east and west.
Walk into a big shopping mall, a zoo or a national park visitor center and you will often find a large map on a stand with a red dot and the words "You are here." Good ones are printed so that the direction you are facing is up on the map. If the food court is ahead of you, it is drawn above the red dot.
That means two such maps in the same building may point north different ways. A map by the east entrance and a map by the west entrance of a mall face opposite directions, so north is up on one and down on the other. Both are right, because each matches the person standing in front of it.
Map designers have found that people get lost less often with maps turned this way. But the maps still print a small north arrow, so a visitor who wants to know which side of the building faces the parking lot to the north can work it out. Reading that small arrow is the difference between trusting the map and guessing.
Car navigation screens and phone map apps in the United States usually let the driver choose between north up and heading up. In heading-up mode the map turns as the car turns, so the road ahead always points to the top of the screen, like looking through the windshield.
Picture a car driving south on a highway in heading-up mode. The top of the screen is south, so north is at the bottom, east is on the left and west is on the right: exactly the upside-down map of this lesson. A passenger who says "the lake is on the left, so it must be west" would be wrong; with the car heading south, left is east.
That is why every such screen shows a small compass mark, often a red arrow or the letter N, that moves around the edge as the car turns. A passenger who checks that mark first can name every direction correctly, whichever way the road is going.
North is a direction on the ground, not a place on the paper. Most maps are printed with north up the page because that is the habit, and the arrow is there for the ones that are not. Read the arrow before you say which way anything is.
The telltale sign is an answer that is right for the paper and wrong for the ground: reading the top of the island map as north puts the lighthouse in the west and the dunes in the north, and every later answer is wrong in the same way.
The other slip is turning only one direction. If north moves, all four move, and they keep their order. There is no map on which north is to the right and east is also to the right.
The arrow on the island map points at the right-hand edge. Place north.
$\text{north: the right}$
Read the arrow first.
Turn a quarter clockwise for east.
$\text{east: down the page}$
The compass turns as one piece.
Place the opposites.
$\text{south: left; west: up}$
Opposite north and east.
Find the island's south end.
$\text{its left-hand end}$
Not its bottom.
On a map printed upside down, the arrow points at the bottom. Place north.
$\text{north: down the page}$
Where the arrow points.
Place south on the page.
$\text{south: up the page}$
Opposites stay opposite.
Turn a quarter clockwise from north for east.
$\text{east: the left}$
From the bottom to the left.
Place west on the page.
$\text{west: the right}$
Opposite east.
Check the order clockwise.
$\text{bottom, left, top, right}$
North, east, south, west.
A map's north arrow points at the $3$ on a clock face. Record it.
$\text{north at } 3$
The right-hand side.
Add three hours for east.
$3 + 3 = 6$
A quarter turn clockwise.
Add three more for south.
$6 + 3 = 9$
Another quarter turn.
Add three more for west.
$9 + 3 = 12$
The top of the clock.
Turn the hours into sides of the page.
$\text{east down, south left, west up}$
Six, nine, twelve.
Check against the table.
$\text{the row where north is right}$
They agree.
Place north on the page.
$\text{the left-hand edge}$
Where the arrow points.
Find the opposite side.
$\text{the right-hand edge}$
South is opposite north.
Check with the clock.
A map's north arrow points at the **bottom** of the page. On that map, which side of the page is east?
Complete the worked solution: picture a clock face on a map. The map's north arrow points at the $12$ on the clock. At which hours on the clock do east, south and west point?
Find east's hour.
$\text{north's hour} + \text{three hours} =$ e
East is a quarter turn clockwise.
Find south's hour.
$\text{east's hour} + \text{three hours} =$ s
Another quarter turn.
Find west's hour.
$\text{south's hour} + \text{three hours} =$ w
After twelve, start again at one.
Check the opposites.
$\text{north and south six hours apart}$
Halfway around the clock.
On a fold-out map of Millbrook, the north arrow points to the left-hand edge. Match each direction to the side of the page it points to on that map.
| the left-hand edge | up the page | the right-hand edge | down the page | |
|---|---|---|---|---|
| north | ||||
| east | ||||
| south | ||||
| west |
Before you can say which way anything is on a map, you have to find the north arrow. There are two marks under the sea on this map: one is an arrow with a point on one end, and one is a plain bar cut into steps. Click the north arrow.
This task has no paper form; do it on a device.
On this map the north arrow points at the right-hand edge of the page. So north is to the right, east is down the page, south is to the left and west is up the page. Click the thing at the **south** end of the island.
This task has no paper form; do it on a device.
A map is printed with its north arrow pointing **down the page**. Fill in which side of the page each direction points to on that map.
| Side of the page | |
|---|---|
| north | |
| east | |
| south | |
| west |
A boat is sailing toward Kestrel Island from the east, looking for somewhere to come ashore. Remember that on this map north points at the right-hand edge, so east is **down the page**. Click the place on the island's eastern side where a boat could land.
This task has no paper form; do it on a device.
An unfamiliar garden map has a north arrow pointing RIGHT along the page, shown by the pointed line near its top. The flag is the entrance. A visitor needs the shelter one square EAST of that entrance. Place the shelter label. The grid's column numbers increase to the right and its row numbers increase up the page, even on this rotated map.
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.
An unfamiliar garden map has a north arrow pointing RIGHT along the page, shown by the pointed line near its top. The flag is the entrance. A visitor needs the shelter one square EAST of that entrance. Place the shelter label. The grid's column numbers increase to the right and its row numbers increase up the page, even on this rotated map.
This task has no paper form; do it on a device.
You can read a north arrow and turn the compass to match it. Tell somebody what goes wrong if you assume the top of every map is north.
19. Your turn: a map's arrow points at the left-hand edge. Which side of the page is south?, step 3
$9 + 6 = 15, \text{ which is } 3$
Six hours is halfway around.