Shortly after starting my Appalachian Trail thru-hike in 2002, I taught myself dead-reckoning navigation using my watch and data sheet. With surprising accuracy, I could monitor my hiking pace, pinpoint my location between known landmarks, and predict my arrival time at upcoming points of interest, like water sources and shelters.
On an as-needed basis during later hikes, I acquired additional skills. During my first off-trail experience, on the Sierra High Route, I learned to proficiently and precisely read a map. On Utah’s Hayduke Trail, I used my compass to track my location in meandering canyon bottoms. I ruled out false summits on the Colorado Trail using my altimeter. And while skiing along Alaska’s Arctic coast, I used GPS to calculate the distance to landmarks ahead, like the shoreline.
When I began guiding learning-intensive backpacking trips, my skills took a giant leap forward. As Aristotle said, “Those who know, do. Those that understand, teach.” I learned to understand better through teaching.
What’s your level of navigational proficiency? Test yourself against this list of essential navigation-related definitions, concepts, and skills. Try to complete each task while out in the field. If you’re shaky on, or unfamiliar with, some of the topics, consider them areas for improvement. Find videos, books, and classes that fill the gaps of your knowledge and skill set, and, most important, practice. To get you started, I’ve linked and embedded a few of my own tutorials.
Topographic maps are perhaps the most essential navigational aid. In many parts of the West, it’s possible to navigate using these maps alone.
- Explain the map’s scale.
- How does the scale correspond to real distances? For example, one inch on a 1:24,000-scale map equals what distance in the field? What about 1:62,500 or 1:100,000?
- Measure the straight-line distance between two points.
- Measure the distance of a meandering trail.
- Measure distance using your finger, the scale-specific ruler on your compass, and your compass lanyard.
- Based on the size of features on the map, predict their approximate scale in the field.
Pro Challenge: Learn the relationship between different map scales and different contour lines (e.g., a 1:24,000 map with 40-foot contours or a 1:63,360 map with 100-foot contours) so that the topographic size of new landscapes does not surprise you.
- What is a contour line?
- What is the contour interval of your map?
- What is the difference between index contours and intermediate contours?
- Identify areas on the map that are flat, moderate, and steep.
- Identify high points, like summits, knobs, and hilltops.
- Identify low points, like lakes, creek bottoms, and dry gullies.
- Give a general overview of the landscape on your map, notably its major ridgelines, drainages, and corridor trails.
- Calculate the vertical change between two points.
- Associate terrain on your map with the terrain in the field.
Pro Challenge: Predict whether a ridge or summit will be passable based on the steepness of the slopes below it. Also, account for where snow is likely to linger.
- On a standard large-scale topographic map (e.g., a USGS 7.5 minute or an FSTopo 2016), what types of vegetation and terrain will you find in areas that are shaded green? How about areas without shading? For your answers, list things like tree types, tundra, tussocks, bogs, slabs, talus, or sand.
- Explain what the variants of blue indicate, including a continuous line, an intermittent line, a solid blue line, and blue stripes.
Pro Challenge: Predict the ground cover or vegetation you’re likely to encounter at particular elevations, on certain slope aspects, and adjacent to specific types of landforms. For example:
- A moderate slope at 8,500 feet on the east side of Rocky Mountain National Park is shaded green on the map. What type(s) of tree(s) will you likely find there?
- On the map, a streak of white cuts through a forest on a steep slope below a 6,000-foot peak in the Cascades. Why? And what will you find there?
- The base of a 1,000-foot sheer wall in the High Sierra is unshaded. What will you probably find there?
Using a mapping platform like CalTopo:
- Import a GPX file.
- Annotate the map with important route notes (e.g., tidbits found in guidebooks, like a trail being poorly maintained or marked, side trails to nice vistas, unmarked springs, etc.).
- Create a track, and measure its distance and vertical change.
- Enter this distance and vertical data into a spreadsheet to create a data sheet.
- Print a topographic map (or map set) at your preferred scale and on your preferred paper size.
A basic altimeter or GPS watch is an essential tool for dead reckoning, which is one of the most useful skills for on-trail hikers.
The fundamental formula for distance is your rate of movement multiplied by time.
- Calculate your average rate using distance and time.
- Convert your rate (e.g., miles per hour) into pace (e.g., 20 minutes per mile).
- Predict how much your rate will be affected by variables like vertical change, altitude, and trail quality.
- Calculate the distance you have hiked using rate and time.
- Calculate your estimated time of arrival at an upcoming landmark by using your rate and the distance to the point.
Particularly in areas with limited visibility and subtle terrain, a backpacking compass is a lifeline, even in modern GPS-dominated times. In more favorable conditions, it can still be used to support your navigational story.
- Explain what declination is.
- What is the declination of your current location?
- If you have an adjustable compass, adjust it for declination.
- Orient the map.
- Find a bearing in the field, and transpose it to the map.
- Find a bearing on the map, and transpose it to the field.
- Find a bearing in the field, and transpose it to the map using both an adjustable compass and a nonadjustable compass.
- Follow a bearing.
You might notice that triangulation does not make my list. To me this seems like a useful technique only after I get lost, and frankly, I find it easier to simply stay found. Plus, if you do get lost, you can locate yourself more quickly and more precisely with a GPS device.
An altimeter watch uses barometric pressure to calculate its elevation and is an extremely useful tool in the mountains.
- Calibrate your altimeter using a known reference point.
- Follow a contour (i.e., cover a horizontal distance without losing or gaining elevation).
- Rule out false summits.
- Climb or descend to a specific elevation where you expect to encounter something, like a trail junction or a creek crossing.
- Pinpoint your location by cross-referencing your altitude against a nearby topographic feature, like a lake outlet or a creek confluence.
Pro Challenge: Before a steep climb, predict your arrival time at the top using your normal rate of vertical speed (e.g., your vertical feet per minute).
When your map, watch, compass, and altimeter are not making sense, resort to the ace up your sleeve: a GPS device.
- Download maps for offline use so your smartphone can function as a GPS (with maps) even without cell service.
- Set your GPS devices and map grids to a consistent geodetic datum and coordinate system.
- Upload tracks and waypoints to your device.
- Extend the battery life of your device by switching it to airplane and battery-saving mode (and, more importantly, by using nonconsumptive tools like your paper map and compass instead).
- Pinpoint your location.
- Create a waypoint.
- Create a route to a waypoint.
- Create waypoints, record your tracks, and export them later as a GPX file that can be imported to a platform like CalTopo.
Pro Challenge: Calculate how long you can run your GPS device before it must be recharged.
Find the overall path of least resistance between two points by accounting for the individual effects of:
- Horizontal distance
- Vertical change
- Ground cover
- Game trails
- Time sinks (like canyons, cliffs and ledges, brush thickets, blowdowns, loose moraine slopes, and deep water)
The best line rarely cuts against the grain of the landscape. Instead, it runs directly with or against fall lines and takes advantage of seams of weakness in the landscape; for example, imagine that a thick patch of willows is blocking you from the other side of a creek. The best line would penetrate this thicket where it’s thinnest, at its seam of weakness. (Animals look for the same such spots—these are often where you will find a good game trail.)
Simplify your route finding by using natural features.
- Follow handrails, like a creek, ridgeline, or shoreline.
- Hike until you run into a backstop, like a creek, trail, or ridgetop.
Find relatively safe lines through areas with natural hazards like:
- Creek fords
- Avalanche zones
This is the final part of a four-part series about navigation. Part one is “A Backpacker’s Guide to Maps.” Part two is “The Gear You Need to Navigate in the Backcountry.” Part three is “How to Master Navigational Storytelling.”