Singletracks members have posted GPS data for nearly 2,000 unique mountain bike trails over the years, not to mention countless updates and additions to existing trail maps. In that time we’ve refined a set of tips and tricks for creating great maps using GPS data and thought now would be a great time to share what we know! Whether you’re mapping your local trail system to create an official trailhead map or you just want to help improve the quality of maps here on singletracks, here are some things to keep in mind in the field with your GPS.

Plan your route

Creating a useful and accurate trail map using a GPS takes a decent amount of planning before you hit the trail, especially for “network” trail systems with multiple connecting trails. Sit down with an existing map of the trails or at least a rough mental image of how the trails are laid out and plan a route that will take you on all the trails with the least amount of backtracking. And for completeness, be sure to hit all connectors and out-and-backs with your GPS in tow. Generally speaking, riding all the trails at once makes it much easier to produce a map than trying to piece together multiple rides over several days.

Dial in your GPS

Most GPS units have a data accuracy setting you can use to set the number of track points that are collected along your route. For best results, I recommend setting your GPS to record a trackpoint every second or at least every 2 seconds. By collecting the maximum number of data points, switchbacks come out looking as smooth as a snake and elevation plots roll instead of stuttering.

Along the same lines, I also recommend slowing down the pace for a mapping ride to make sure the GPS is tracking with the trail. It’s easy to get ahead of your GPS on a fast descent and your map will miss out on details along the way. If you notice your unit loses its satellite signal during the ride, stop and wait to reacquire the signal – you’ll thank yourself later.

Mark important features

Out on the trail it’s a good idea to mark certain features using the waypoint function on your GPS unit. You may want to include some waypoints on your finished map (like trail features or water fountains) while other waypoints can be useful reference points when you’re editing your map at home (trail intersections).

Admittedly, marking waypoints on many GPS units can be quite a chore, especially if you decide to name the points or add notes via the GPS. I usually skip the names and notes when I’m on the trail, instead making a mental note whenever I mark a waypoint. If you use a GPS fitness device without a dedicated waypoint button, you can simply press the “Lap” button to quickly add a marker (it will be labeled Lap 1, Lap 2, etc.).

Don’t let your GPS data go stale

Now, after you’ve collected your GPS data in the field, it’s time to clean things up on your home computer. Be sure to do this as soon as possible because all those mental notes you took on the trail tend to fade over time.

First, go back and add notes to any waypoints you marked along the trail. I prefer to use my GPS program’s “description” field for notes since the waypoint name field can be limited and many GPS units end up truncating the name anyway.

Next, follow the track on the screen and think back through the ride. Is that short line on the map there because you turned down the wrong trail and did a 180? Cut that section out. Does it look like a tight network loops back on itself when in reality it doesn’t? Remove the wayward track points to show the trail more accurately.

Finally, take a look at the elevation profile. Many GPS units have trouble producing accurate elevation numbers (smartphones and less expensive devices especially) so if something looks off, it probably is. Fortunately there are many online tools, including this one, that look up the correct elevations for your track file to help smooth things out.

The result

Once you’ve collected your data and cleaned it up a bit, it’s time to share! The great thing about having solid GPS data is there are so many uses for it: overlaying in Google Earth to visualize your ride, creating large scale maps for the trailhead, sharing online, or even providing the data to local emergency responders and land managers.

Accurately mapping a mountain bike trail takes just a bit more effort than strapping on a GPS and going for a ride but in the end the result is worth the extra effort!

What tips do you have for collecting killer GPS tracks on the trail?

# Comments

  • RoadWarrior

    Love the rubber bands. I keep a tether on mine so I don’t have to hunt for it in the weeds in the event of a crash.
    IMO; for well marked trails few waypoints are needed, for poorly marked or non-existent signage, more waypoints are needed.

  • Jarrett.morgan

    This is a great post. Anyone that plans to start trying to map trails should take a look at this post first.

  • Jared13

    I’m hoping to start mapping the trails out here once I get cleared to ride again. Thanks for all the tips!

    Is there a program I should download to make editing the GPS track easier? I have a Garmin but I haven’t looked into editing anything yet.

  • mtbgreg1

    Good question on editing the gps track. What do you use on your Mac, Jeff? Just gpsapp.net, or something more elaborate?

  • RoadWarrior

    I use TopoFusion, lets me do anything I need to with tracks, or waypoints, also great for creating networks from multiple GPS tracks. Also dozens of map overlays, satellite, or combinations.

  • chukt

    I use Garmin Basecamp to edit tracks on my mac. It is simple to edit.

    Then I use TrailRunner to merge multiple tracks as a sort of trail database to differentiate between good trail and game trails and “kind-of” trails and bushwhacks.

  • trek7k

    On the Mac I use MacGPS Pro which is pretty bare bones and I don’t really recommend it for others. Garmin Basecamp is probably a better choice and it’s free! It’s basically the same as Garmin MapSource (PC) and allows you to edit individual track points, reverse tracks, etc.

    TopoFusion for PC is really awesome so I run Parallels on my Mac to access the program. I also use online tools like GPSVisualizer and of course GPSApp.net since they’re cross-platform.

  • Bubblehead10MM

    Good post. I do a lot of planning most of the time before mapping. Most of the trails I’m getting already have pretty good maps posted online some where, and a little goggling gets me to a brochure or some thing I can print out. It’s invaluable to have a map if you intend to make a map. Alliteratively sometimes snapping a pic of whatever is at the trail-head on my phone will do the trick. I’m looking forward to trying out some of the online, and software tools Y’all have named. GPSAPP has kinda been disappointing so far, and the only thing I’ve been using is GPX_Editor.

  • Jared13

    Thanks for the tips everyone! I’ll have to try them out soon and see which one works best for me.

  • RoadWarrior

    We covered the uploading, but where the fun comes in is downloading. Yesterday downloaded all the tracks in the the area of Colorado Springs I was going to ride. Imported them into Topo Fusion, told it to make a network, Just like magic had a 49 mile trail system around the Gold Camp Rd area. Imported this file into my DeLorme maping program, added a few waypoints/ notes, then uploaded the file to my PN-60 and I was ready to ride with a complete map.

  • jnieurzyla

    I am looking for a accurate track logger, my Garmin nuvi 765 does it, buts not so good, I also have to do the secret login to increase it 1 sec tracks, but its a fiddle, and would prefer a machine designed to do the job properly at 1 sec or more and a large memory for the logs created.
    Any ideas or suggestions please?

    • jeff

      Accuracy can depend on a number of factors including the GPS signal strength which can be blocked by things like cloud cover, trees, mountains, etc. But the Nuvi 765 really isn’t meant for logging your routes anyway–it’s really for navigation on streets.

      If you have a smartphone, I recommend first trying a GPS app like Strava or Runtastic’s MTB app. If you want a dedicated GPS unit, the eTrex series from Garmin is a good place to start. Also look at Garmin’s cycling-specific units in the Edge series.

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