A bearing is a direction given as an angle, measured clockwise from north, and written with three figures. Questions use bearings to describe where one place lies from another, so the starting point and the north line both matter.
This lesson follows grid references in map reference and direction.
How do bearings work?
Stand at the place you are travelling from. Draw a north line straight up from it. Then measure the angle clockwise from that north line to the line pointing at the other place.
Due north is 000°, due east is 090°, due south is 180° and due west is 270°. A direction between east and south, such as south-east, is 135°.
The back bearing is the bearing of the return journey. The two directions are opposite, so they differ by 180°.
Which north are we using?
A map has more than one north. Grid north follows the vertical grid lines. Magnetic north is where a compass needle points, and it differs from grid north by a small angle that changes with place and year.
The map legend usually gives that angle with a date. For exam questions, use the north the question states. If none is stated, say which one you assumed.
Worked example
On an invented map, town B lies from town A so that the angle from A’s north line, clockwise to B, is 40°.
Step 1, from A: the bearing of B from A is 040°.
Step 2, reverse the journey: the back bearing is the bearing of A from B. Since 040° is less than 180°, add 180°: 40 + 180 = 220°.
Step 3, check with a sketch: at B, draw a north line. B is north-east of A, so A is south-west of B. A bearing of 220° is between south (180°) and west (270°), which matches south-west.
The mistake to watch for
A common slip is to measure from the wrong place.
Mistaken answer: the bearing of A from B is 140°.
The student subtracted 40 from 180, treating the angle as if it were measured from south. A bearing is always measured clockwise from north at the starting point.
The correction is to redraw the north line at B and measure clockwise. Adding 180° to 040° gives 220°, and the sketch agrees.
Check yourself
All directions here are invented.
1. A lighthouse is due south-east of a jetty. Give the bearing of the lighthouse from the jetty.
Show answer
South-east is halfway between east (090°) and south (180°). 135°.
2. The bearing of a hut from a camp is 300°. Find the bearing of the camp from the hut.
Show answer
300° is more than 180°, so subtract 180°: 300 − 180 = 120°.
Check: 300° points north-west, so the return is south-east, and 120° lies between east and south.
3. A bearing of 225° is between which two compass points, and what single direction is it?
Show answer
225° is halfway between south (180°) and west (270°), so it is south-west.
Where this leads next
Next, practise relating a map symbol to its legend, because a legend also tells you what the north arrow and scale mean. The mixed practice set combines bearings with grid references.
If you can calculate a bearing but lose track of which point you started from, a teacher in online one-to-one Geography tuition can help you build a quick sketching routine.