How to use GPS track files!
What is a Track File?
A track file is a list of sequential coordinates that's created as a GPS
unit rides along with the bike. Each listing is a point in 3-D space, containing
latitude, longitude, and elevation. Depending on the bike's speed, and the turns
of the trail, the points may be close together (separated by a couple of feet)
or widely spaced (200-300 feet).
What is a Track File good for?
If you have a track file for a specific trail, your GPS unit can display it
on the map of the area. As you ride along, the little marker that says "I
am here" moves along the line of track points. If the little arrow moves
away from the line, you just took a wrong turn. With a track file, you just
follow the little line, and you're retracing the path the original rider took.
Even on the most complex trail system, you can't get lost.
How is a Track File created?
You turn your GPS unit on, clear out any previous data points, then ride the
trail. As you reach the end of the trail, you save the track data to a file
within the GPS unit.
Are Track Files a perfect representation of a trail's layout?
No. On some trails, for example Bear Canyon in the south fork of American Fork
Canyon, the slope of the mountain is too steep and the trees are too thick. For
over a mile, there's no satellite reception. Sometimes, for reasons of its own,
the GPS unit suddenly plots a point that's waaaay off the trail. And often, the
GPS track just jumps right across from Point A to Point C, bypassing a curve or
corner. But, within these limitations, the track file will fit pretty well as
you ride, and should keep you on the right path.
How do I use somebody else's Track File?
If you don't ride with a GPS unit, you can still benefit from track data. It
allows creation of a very accurate map (but only as accurate as the data in the
track file). Once a track file is created by the GPS
unit, it can be uploaded to a computer. The line created by the track file can
be superimposed upon a satelite photo or topographical map to create a map that
another rider can follow. If you have a whiz-bang mapping program, you can use
the track file to create a superb high-resolution map in your favorite format.
If you have a GPS, you can load the track file into your unit and follow the
track line, just as if your own GPS had created the track. Now comes the tricky
part -- getting somebody else's track data into your unit.
Is there a standard "Track File" format?
Unfortunately, no. Almost every GPS manufacturer uses a different format for
storing and transferring track data. So you need a middleman -- a program on
your computer that can import a downloaded track file from the UMB web site,
then export that data to your GPS unit.
What do I need to BUY to use Track Files?
You need a GPS unit, with a cord that connects it to your computer, and you
need a program on your computer that can process the file. First, install the
"middleman" program on your computer. Examples include Garmin
Mapsource, National Geographic TOPO, and Topofusion. (The Topofusion demo
version is free.) Now connect your GPS unit to the computer, and make sure they
can talk to each other.
How do I create maps?
Start your "middleman" program, for example National Geographic.
Download a track file from this web site. Open the file. You should see an
outline of the trail. Select the type of background you want (relief, shading,
detail, resolution, space photo vs topographic background, etc). Select the area
you want to print as a map. Include nearby roads if you want. Fiddle until
you've got the biggest, highest-resolution map possible. Now send it to your
printer.
How can I get a Track File into my GPS unit?
Start your "middleman" program. Download a track file from this
web site. Open the file. You should see an outline of the trail. Somewhere in
the program, you'll see an option to "Export to handheld" -- or
something similar. Export the file, then check your GPS unit's track menu. You
should see the file there. To display the track as you ride, follow the
instructions specific to your unit.
So where do I get these files?
We have a few track files on this site. You'll find the download link on the
specific trail's review page. (Go to the trails index, find the trail you want,
and click on the link to that page.) It's usually near the bottom of the page,
along with options for other trail resources. If you don't see the track file
there, try our forum. There's a section on the UMB forum where you can upload or
download GPS data.
Got a good track file for a trail? Send it to us as an email attachment! [Email Link]