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Spot Heights
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Spot heights are the small black numbers on the map that indicate altitude in metres. Each number will usually include a small black dot (and sometimes a black circle). The dot is the position of the spot height. Spot heights can be used to indicate which way to go or not to go.

In the most simple form of spot height navigation you will be presented with a list of numbers. This will mean you must select, usually, the shortest route that joins them together. Never be tempted to pass through other spot heights that are not in the list, the navigational rules often state that if a specific feature for navigation is used - in this case, spot heights - then all others should be ignored.

Particularly if the route covers a large area, make sure you pass through the correct spot heights; there may for example be two with the same number only one of which should be used.

A spot height number doesn't always mean that it's accompanying black dot is present. The requirement is usually to pass through the dots; if you can't visibly see a dot then you may need magnification to confirm it's there (some are very feint) or it's possible that you've found the wrong number - look for another.

Make sure the black dot is on the road of your route. Those offset at a junction, may or may not be considered to be on the junction. And, are spot heights in the middle of dual carriageways on both roads or neither?

Don't confuse spot heights with gates. A gate (a straight line) and a Spot Height (a dot) can be easily confused in poor lighting.

Since spot heights are numbers, there are many ways that their values can be disguised (See the section on disguised numbers). One unique method used for spot heights is defining the navigation by one large number which is the summation of the spot heights to be visited.

Triangulation points are not usually defined as spot heights. Check the regulations for the event.