Even in this modern era of GPS navigation and routing, the compass and map remain essential tools of traveling beyond roads. With even the most sophisticated GPS units, batteries

can run flat, satellite signals can be lost, and the GPS receiver itself could be damaged in a fall. You may navigate the backcountry for days at a time without thinking about your compass, but if a blizzard blows in or your GPS takes an unexpected drop in the lake, your compass will become the most valuable tool in your pack.

For the outdoorsman, the ability to navigate with map & compass is a crucial skill. You may not use it every day but there could come a time when it can get you out of a real jam. Compass are also a great companion to a GPS unit. A GPS can only tell direction when it’s moving, which means if you want to follow a bearing then you must leave the unit on or power it up frequently for a position fix. With your compass in hand, you can take the bearing from your GPS and turn it off, then set the bearing on your compass and off you go, only turning on the GPS for an occasional fix or course correction. The power saving could be significant on a long trek with little opportunity to recharge the GPS.

Compass Types

Compasses come in two basic types: needle compasses and electronic compasses. The most common type is the needle compass, which uses a magnetized needle that aligns

itself with the earth’s magnetic field. The needle is usually mounted in a clear, liquid filled housing that quickly steadies the needle and enabling accurate bearing readings. For the day hiker or light backpacker, a simple needle compass is sufficient. For deep backcountry or offtrail travel a more advanced unit may be worthwhile. The advanced features include declination adjustments, sighting mirrors, map scales, magnifiers, and more. Electronic compasses offer digital displays for precise bearing measurement, but require calibration and rely on batteries for power.

Compass Features

These are some of the important features found on needle type compasses:

• Declination Adjustment Your compass needle points to the magnetic north pole. In a perfect world this would be the same as the geographic north pole, but it’s not. The difference between magnetic and true north is called “magnetic declination” and must be accounted for when navigating with a compass and a map. Some compasses include an adjustable declination arrow that you set to the declination indicated on your map, this simplifies navigation.
• Sighting Mirror When adjusted to reflect the compass needle you can simultaneously sight through a notch in the lid to your distant landmark. This makes it easy to take accurate bearings. The mirror can also be used for signaling in an emergency by reflecting sunlight back to your rescuers or search party.
• Global Needle The strength of earth’s magnetic field is not uniform. A compass designed to swing freely in North America may tilt severley or drag in other regions of the world. Compasses with a global needle compensate for variation in the magnetic field strength and work equally well anywhere on earth.
• Bezel Degree Markings Most compasses use a 2 or 5 degree marking interval on the bezel. Larger and more carefully produced units can fit 1 degree resolution markings. In most cases 2 degrees is still plenty accurate because you can interpolate between the marks.
• Map Scales Used to make map distance measurements easier and faster. The common U.S.G.S topo maps are on a 1:24,000 scale where 1″ on the map equals about 3/8 of a mile on the ground. A 1:100,000 scale shows less topographic detail and 1″ on the map is about 1.5 miles on the ground.
• Clinometer Used to measure vertical angles. This is useful for estimating the steepness of a hill.
• Liquid Filled Housing A non-freezing liquid is used to damp the needle’s swing and jiggle more quickly than in an air filled housing. At high altitudes or cold temperatures, the liquid can contract, forming a bubble. The bubble doesn’t affect the compass’ accuracy and will disappear when conditions return to normal.

Other features include a luminous marks at the cardinal points and luminous bezel markings for night navigation. A lanyard to keep the compass tethered to your wrist, essential for racing or orienteering. A magnifier for discerning tiny map details.

Outdoor Fun with Map and Compass

Orienteering is a exhilirating sport combining cross-country travel with map and compass skills. You use a map and a compass to locate a series of points called “controls” shown on a specialized topo map, choosing routes-which may or may not follow trails-that will help you find all the controls and get to the finish in the shortest amount of time. Each control is a distinctly mapped feature, such as a hilltop, a distinctive tree or boulder, or stream junction and is marked with an orange-and-white flag, or “bag”. Just Google “orienteering” to find out more.

Recommendations
I’ve used a lot of different compasses, but I continually reach for my Brunton Classic (shown above). The Brunton classic fits nicely in my hand, is inexpensive, and is feature packed for the price. Important features include a no-tool declination adjustment, clinometer, and 2 degree bezel gradations. It’s a solid performer for the beginner or experienced navigator.


For learning the art and skill of navigating with map and compass I have to recommend the classic text, Be Expert with Map and Compass: The Complete Orienteering Handbook by Björn Kjellström.