On every Ordanance Survey map is a scale bar which converts the space on the map to km or miles. So a scale bar that says 1:25 000 then it means 1 cm is equivalent to 25 000 cm which is 0.25 km.
A quick way to measure is to count each square you go across. Then you can use your scale to find out how many km the journey is. Measuring in straight lines is called 'as the crow flies'.
It's usually not possible to travel in a straight line. If you lay out a piece of string along your route and then measure the route, you can find then convert your journey to km.
1 of 3
Understanding Scale
It isn't possible to draw maps in real scale because it wouldn't all fit on the map. So they draw things in ledgible sizes and then use a scale to convert the sizes they have used to real life sizes.
There are two types of maps: small scale maps and large scale maps. Small scale maps are good for when you're walking or travelling by car because they cover large areas of land. Large scale maps are better for looking at buildings in detail as they only cover smaller areas of land.
2 of 3
Relief and Countours
Maps are flat, like any piece of paper, but the actual world around us is quite hilly. Maps can't show this literally as the piece of paper is flat but to impersonate the hills, they use contour lines.
When contour lines are close together it means the land is very steep. The furthur apart the contour lines are, the flatter the land is.
When you're travelling across steep areas will add time onto your journey. Naismith said that you should allow an extra minute of walking for every 10 metres of height that you climb. Contour lines are usually drawn at 10 metre intervals on a 1:50000 scale map and at 5 metre intervals on a 1:25000 scale map.
Comments
No comments have yet been made