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Choose your map scale

 One of the regular questions I'm asked is what map scale should one practice with?  Well it every much horses for courses really; if you want to pursue orienteering as a sport, then you need to get used to large map scale (1:5000 or 1:10000 typically although others are used).  If exploring the wilds of the Scottish Highlands is your thing, then many seasoned veterans would suggest a 1:50000 map.

Most of  us, however, fall between these two extremes and on the Silva Navigation School courses we tend to concentrate on 1:25000 map scale, where 1 cm on the map is the equivalent of 25,000 cm (or 250m) on the ground.  In the UK we are lucky in that we have excellent mapping at our disposal from the Ordnance Survey to Harvey Maps, and whilst their maps look different from each other, both are well mapped and contain masses of detail that we as outdoor users can use to safely navigate by.

Get familiar with your map

OS maps, of course, cover the whole of the country whilst Harvey maps tend to be restricted to major outdoor areas and long distance and recreational routes.  If you find yourself in an area covered by both, I would certainly advise you go out and practice on both.  Familiarity with different maps is always useful especially if you ever walk abroad.  The quicker you can get used to a different looking map the better, and you can spend your time working out how accurate the map and therefore how much you can trust it!

OS 1:25000 map and its equivalent Harvey map below
Harvey 1:25000 map scale

Maps are only as good as the last time they were surveyed and printed and although the OS are said to effect over 10,000 changes to their mapping every week, errors inevitably creep in.  I know of houses that have been up for over 40 years that are still missing from maps whilst the neighbouring housing estate built eight years ago is on.  

You'll find lost of inconsistencies on maps the more you begin to look at the detail.  One error on the map won't get you lost, however -  check the detail around it to see if the rest of the map in this area is correct or if you're if you're in the right place!

At the Silva Navigation School, we teach you how to choose the right map scale and how to get the most from your map.  We show you how much useful navigational details there is and how you can use it to your advantage.  Why not look through the dates now, and book a course.  

In the meantime Happy Map reading.