ewoc.org

Eastern Washington Orienteering Club

Using A Compass With A Map


Turn your body until the magnetic needle lines up with the bezel…

Stacks Image 6
The raised ring on the compass is called the bezel, and it rotates independently of the baseplate. Leave the baseplate lined up with your route and turn the bezel until "N" on the ring points toward north on the map.

The center of the ring is conveniently transparent so you can see the map through it. Adjust the bezel until the painted lines in it are parallel with the north-south lines on map.

This step effectively records an angle on your compass — the angle between north (0°) and your intended direction of travel.

Bonus Details

The distance between magnetic north lines is consistent (often 250 meters, real world) so that you can estimate distances quickly
Compasses point to magnetic north. In Spokane that means your compass will point about 14-1/2 degrees east of true north (the line that streets generally correspond to). That "error" is known as declination — as in "14-1/2 degrees east declination."
The declination varies by region, and slowly over time. 40 years ago, the declination in Spokane was about 5 degrees greater.