Direction, scale, distance and height

Direction

Try to remember the main compass points by using a mnemonic, eg

Naughty Elephants Squirt Water - North East South West

sixteen point compass

The four main points of the compass are north, east, south and west. Half way between each of these there are four other points: north-east, south-east, south-west and north-west. This makes an eight-point compass. There are a further eight points between these - remember the names of these are a mix of the two closest compass points but they always start with the main compass point, ie north, east, south or west.

Ordnance Survey maps are always printed so that north is at the top of the map.

Scale and distance

Example of a scale bar with one two centimeters for every one kilometer

Most maps have a scale. These help us to work out distances on maps. This is given by the scale statement (eg 1:25,000) and/or by showing a scale bar.

The scale shows how much bigger the real world is than the map. If the scale is 1:50,000 it means that the map is 50,000 times smaller than the real world. For example, every 1 cm on the map represents 50,000 cm in the real world.

Height on maps

Maps show height in a number of different ways:

Spot heights and triangulation pillars

This map extract shows exact heights by a black dot with a number next to it. The number is the height above sea level in metres. The blue triangle represents a triangulation pillar; the networks of concrete pillars found in the UK that were used to make maps.

Ordnance Survey map showing Snowdonia peaks

Contours

These are lines drawn on maps that join places of the same height. They are usually an orange or brown colour. Some contour lines have their height above or below sea level written on them. It is possible to use them to see the shape of the land - if contour lines are close together the slope is steep, if they are far apart the slope is gentle. Contour lines are usually drawn at 10 metre intervals on a 1:50,000 scale map and at 5 metre intervals on a 1:25,000 scale map.

Ordnance Survey map showing contours

Layer shading

Maps are sometimes shaded to show the height of land.

Layer map of Mt Snowdon
Credit: CROWN COPYRIGHT.