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Eastern Washington Orienteering Club

Using A Compass With A Map


The Orienteering Map

This page, and the ones that follow, will describe the peculiarities of an orienteering map and show you how to efficiently use a compass with one. Print out this PDF copy of the map we're using as an example if you want the full hands-on experience.
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Orienteering maps are convenient for using with compasses because they are drawn in alignment with magnetic north. North is always toward the top of the page. Like the map at left, many orienteering maps have prominent magnetic north arrows for reference when you have the map partially folded.
In our lesson, we're going to imagine that we are at control point 4 and want to follow a compass heading to control 5.

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.