Canada Topographic Maps

Orient your Topo Maps via 4 Methods - Help

How to Orient a Map to Correspond to the Ground

Orienting a Map

Orient your Topo Maps via 4 Methods - Help

A map is oriented when it is made to correspond to the ground it represents. Remember, on a topographic map, north is the top of the map. There are four ways to orient a map:

1. Orienting by Compass

With a protractor, draw a magnetic north line anywhere on your map. The declination diagram in the margin of the map will give you the direction and size of the angle between grid north and magnetic north.

Do not use the margin diagram itself as the angles are often exaggerated by the cartographer so that the numerical values for the angle can be inserted.

Place the compass on the magnetic north line and turn the map and compass together slowly until the needle points to magnetic north on the map.

2. Orienting by Distant Objects

If you know your position on the map and can identify the position of some distant object, turn the map so that it corresponds with the ground.

3. Orienting by Watch and Sun

In the Northern Hemisphere: If Daylight Saving Time is in effect (in summer), first set your watch back to Standard Time. Place the watch flat with the hour hand pointing toward the sun. True South is midway between the hour hand and XII. True North is directly opposite.

Note, this method is very approximate.

4. Orienting by the Stars

In latitudes below 60° North, the bearing of Polaris is never more than 2° from True North.

You can identify the North Star, Polaris, by drawing an imaginary line through 2 particular stars of Ursa Major.

Ursa Major and Cassiopeia point to Polaris. These two constellations revolve counter-clockwise around Polaris.

 
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