When I first started exploring wilderness, a map and compass was the best way to navigate in unfamiliar country. Mostly because it was the only way to navigate in unfamiliar country. Today, my wayfinding tool kit contains a mix of classic instruments and modern gadgets. Let’s take a walk-through, starting with that old reliable, the topographic map:
Those squiggles on a map are called contour lines. Each one corresponds to a change in height. With practice, I learned to visualize how the features they represent look from the side. So I can mentally translate this:
into this:
To find your position on a map, all you need is a couple of such landmarks to take bearings (angles) from using your compass. Transfer those bearings into lines onto your map and where they meet is where you are. If you’re already somewhere along a known line like a shore line or trail, you only need one compass “shot” to cross it and show your position.
No recognizable landscape feature? No problem – as long as you’ve brought your altimeter. Every contour line follows a specific elevation. So if you know you’re at 300m, you locate the corresponding contour line on the map, find where it intersects the trail to Black Fly Bog, and there you are.
It’s easy in theory. And usually in practice. But sometimes there are no distinctive landscape features or they’re masked by snow or fog. Local iron deposits can mess with your compass needle. Weather-related pressure variation can fake out your altimeter. Plus, many parts of Canada have no significant elevation changes for miles.
That’s why ever since GPSs became even semi-portable, I’ve been all over them. Being an early adopter had its price: my first GPS was the size of a Korean War walkie-talkie, and cost more than a grand.
Old-timey GPSs lacked built-in maps, so you had to transfer the numerical co-ordinates they gave you to a paper map to see where you were, and manually input the co-ordinates for any location you wanted to go. That meant you couldn’t see your position or progress in real time. Setting up a route that didn’t try to lead you across impassable obstacles, as the crow flies, demanded the tedious entry of multiple waypoints.
Modern GPSs solve all those problems with built-in or uploadable maps. Some map programs let you tilt the point of view from overhead to ground level, showing you the landscape profiles I used to have to conjure up in my mind’s eye. Many let you integrate the maps with satellite imagery. And some let you fly your proposed routes in 3D, like an off-road version of Street View.
A lot of newer phones also have true GPS chips that receive satellite signals (as opposed to faking it with positioning derived from cellphone towers). It’s smartest to use an app that lets you download and store maps in your phone’s memory. That way, you’re not map-less when you can receive satellites but are beyond cellphone coverage.
As a confirmed gadget-weenie, I love me my electronic toys. But batteries die and LCD screens sometimes fail the drop test. So I practise regularly with a compass and hardcopy map, and always have them in my pack. I think of them as the original wireless navigation instruments.
Want to get good with a map and compass? Check out Philip’s recommended reading. And get fully equipped to stay found here.
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