How to Read Magnetic North on a Compass

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It may come as a shock that the "N" needle on your compass doesn't always point north. Not true north--the north marked on a map--anyway. The compass needle does always point to magnetic north, however. The problem is that magnetic north--the northern pole of the earth's magnetic field--is in constant motion and doesn't always match up with the true or "assumed" northerly direction on a map. If you can calculate the difference between magnetic north and true north--known as magnetic declination--you can figure out where you are on a map; but the first step to doing this is using your compass to determine magnetic north.

Rotate the your compass bezel (if it is adjustable; not all are) until the 0/360 degree mark, or the letter N, lines up with the indicator arrow or sight line.

Hold the compass in front of you, horizontally oriented, indicator arrow or “N” pointing straight ahead of you.

Turn to the right or the left, as necessary, until the compass needle lines up with the indicator error or the “N” indicator and the 0/360 degree mark on the compass bezel. Most compass needles will have a small “N” on the end of the needle that points toward the north (the other end, obviously, will point toward the south).

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