Hiking is a great way to enjoy nature, explore new places, and stay fit. However, hiking also comes with some risks, such as getting lost or injured. That's why it's important to have some basic navigation skills and tools when you hit the trails.
Pictured: SUUNTO A-10 Compass, a great affordable option for a reliable compass, along with the National Geographic Lake George/Sacandaga Region Trail Map
One of the most essential tools for navigation is a compass. A compass is a device that shows you the direction of magnetic north, which you can use to orient yourself and find your way on a map. A compass doesn't need batteries or signal, so it's reliable and easy to use.
But how do you use a compass while hiking? In this article, we'll explain the basics of compass navigation, including how to read a compass, how to adjust for declination, how to take bearings by map or sight, and how to follow them in the field.
A compass has several parts that you need to know before using it. The most important part is the magnetic needle, which is a red-and-white arrow that always points towards magnetic north. The red end of the needle is called north-seeking pole or simply north.
The second part is the baseplate, which is the transparent flat surface of the compass. It has a rectangular shape and usually has at least one straight edge that you can use to align with map features or draw lines on a map. The baseplate also has markings for measuring distances and angles.
The third part is the rotating bezel or housing, which is the round plastic bubble that contains the magnetic needle. The bezel has degrees marked from 0° to 360° around its edge. These degrees are used to measure directions or bearings on a compass.
The fourth part is the direction-of-travel arrow or index line, which is an arrow on one end of the baseplate that points away from you when you hold the compass flat in front of you. This arrow shows you which direction you need to go when following a bearing.
The fifth part is the orienting arrow or outline, which is an arrow inside the bezel that rotates with it. This arrow helps you align your compass with your map or your bearing.
Before using your compass for navigation, you need to adjust it for declination. Declination is simply the difference in degrees between magnetic north (where your needle points) and true north (where maps are oriented). Declination varies by location and time because of changes in Earth's magnetic field.
If you don't adjust your compass for declination, you'll get inaccurate readings and directions on your map or in the field. For example, if declination in your area is 10° east (positive), then magnetic north will be 10° east of true north on your map. If you don't correct this difference on your compass, then every bearing you take will be off by 10°.
To adjust your compass for declination, you need two things: first, know what declination value applies to your area; second, have a way to set this value on your compass.
You can find out declination value by looking at your map legend (if it's up-to-date) or checking online sources like the NOAA website.
To set declination value on your compass depends on what type of model you have: some have an adjustable screw that lets you rotate the bezel until it matches declination value; others have fixed markings that show common declination values; others have no adjustment mechanism and require manual calculations.
If your compass has an adjustable screw, simply loosen it and turn the bezel until the orienting arrow points to declination value (positive or negative) on the degree scale. Then tighten the screw again. Your compass is now adjusted for declination and ready to use.
If your compass has fixed markings, find out which one corresponds to declination value in your area. Then align this marking with the index line when taking bearings by map or sight. Your readings will be automatically corrected for declination.
If your compass has no adjustment mechanism, you'll have to add or subtract declination value from every bearing you take by map or sight. For example, if declination is 10° east (positive), then add 10° to every bearing you take by map, and subtract 10° from every bearing you take by sight. If declination is 10° west (negative), then subtract 10° from every bearing you take by map, and add 10° to every bearing you take by sight.
There are two ways you can take bearings with your compass: by map or by sight. By map means that you use your map to find the direction of your destination from your current location. By sight means that you use your compass to find the direction of a visible landmark in the field.
To take a bearing by map, follow these steps:
To take a bearing by sight, follow these steps:
Once you have taken a bearing by map or sight, you need to follow it in the field to reach your destination or identify your location. To follow a bearing in the field, follow these steps:
A compass is a valuable tool for navigation while hiking, especially in remote or challenging areas where other devices may fail or be unavailable. By learning how to read a compass, adjust for declination, take bearings by map or sight, and follow them in the field, you can improve your orientation skills and confidence on the trails. Remember to always carry a map and a compass with you, check your declination before using your compass, verify your compass readings with other sources of information, and keep your compass away from metal objects that can affect its accuracy. With these tips and some practice, you'll be able to navigate with a compass like a pro.
See more posts in the Hiking Tips category.