How to really use a GPS for walking

Garmin Etrex-Vista HCx

GPS with on-board map, showing waypoints

Many hikers have told me that they have a GPS but never use it. At first I couldn’t understand why, because mine has become an essential tool. Gradually, I realised that they had a limited vision of what it was for.

Some used their GPS like a first-aid kit. It stayed in the rucksack until they had a problem.

Others used it like Ariadne’s thread. They carried it around, switched on, but only consulted it if the fog descended and they needed it to find their way back home.

After a few months, the GPS no longer even made it into the rucksack.

Yes, a GPS can be used like a first-aid kit or like Ariadne’s thread. But that’s missing the point. A GPS is not merely a navigation tool. It can be used to improve walking. It can be used like a guidebook. Here’s how.

GPS with waypoints

Detail of the GPS screen. From top to bottom: 1824m = height above sea level ; 0394759 x 4724803 = coordinates; 534m = distance to arrow; 052 1 etc = waypoints along path; 300m = scale (can be enlarged to 20m).

Off the beaten path with a GPS

When I go hiking I often avoid the standard paths with their ubiquitous waymarks and frequent crowds. There are many more paths marked on maps: the only problem is finding them. Because they are little used, they are often hidden.

This is where a GPS comes in. But not on its own. The salesmen won’t tell you, but a GPS on its own is next to useless. You also need GPS compatible maps on your computer (which you can transfer to your GPS). Some of the maps cost as much as the GPS again! But some very good maps can be downloaded for free, see the Open Street Map project and Topo Pirineos (for the Pyrenees), for example. And you need Google Earth, but that too is free.

GPS maps

What I do is to look at printed guides, paper maps, and the GPS compatible maps on my computer. Then I define the path I have chosen on my computer screen, clicking on the map (to create waymarks) every 200m or so. Next I click on “view in Google Earth”. Afterwards, if the path I have created looks interesting, I transfer it to my GPS.

GPS maps and Google Earth

Google Earth is the killer partner application for a GPS. Once I have imported the waymarks into Google Earth I can see if the path still exists and what the walk will be like in 3D.

In the example below, I was intending to walk from Almachar (in Andalucía) along the Colada de Comares. Most of the track was clearly visible in Google Earth, but at one point it disappeared completely.

Topo España

The Colada de Comares track as shown in Topo España GPS map on my computer

 

Google Earth GPS waypoints

The same area on Google Earth: the track can be seen from 031b to 032, but afterwards it disappears

So, having identified a problem, I chose another route.

Wikiloc (wikiloc.com)

This is another complementary tool. The website houses thousands of GPS tracks which have been recorded by walkers around the world. They can be downloaded, imported into GPS software on a computer and transferred to a GPS.

Note: Wikiloc is a bit like Wikipedia: the quality of the information is variable. I have followed downloaded tracks only to find myself straying away from the correct path, just as the person who recorded the track must have done. Although there is an area in Wikiloc where comments can be made on uploaded tracks, it is rarely used.

Incredible synergy: Wikiloc, GPS software and Google Earth

In 2010 I walked with a friend from Viadós to Estós in the Spanish Pyrenees, recording the walk on my GPS, Back home, I uploaded the track to my computer. This is the route taken…

GPS trace of walk from Viadós to Estós

GPS trace of walk from Viadós to Estós

 

… and this is the profile of the trail.

GPS profile

GPS profile. Note: the vertical scale is exaggerated

 

I then uploaded to Wikiloc to share with anyone who might wish to walk the same track – here.

 

Viadós-Estós in Wikiloc

Viadós-Estós in Wikiloc

Viadós-Estós as seen in Google Earth

… and this is the same track in Google Earth

Looking at Google Earth, I can see that we set out at 7:36 and arrived at 13:36

virtual walking on the GR11

This is where we were at 10:37.

When I am feeling really brave I fly along paths in the Google Earth flight simulator. This has taught me that walking in the mountains is safer than flying an F-16.

Limitations of GPS for hiking

Some walkers claim GPSs are dangerously inaccurate: “If I had gone where the GPS told me, I would have walked over a cliff.” I have no patience with this argument. Just because I have a GPS in my hand doesn’t mean I have left my common sense at home. Try finding an exact point on a cliff edge using a 1:25,000 map and a compass and see if you don’t walk over the cliff.

More to the point, if you can’t read a map, a GPS is useless for rambling. Navigation is a difficult art. I don’t trust my GPS, I don’t trust my map, my compass, the local shepherd, not even my eyes, and certainly not my instinct. It is only by putting all these things together that I normally manage to stay on the trail.

My GPS equipement

Garmin Etrex HCx GPS, Vista Garmin Mapsource 6.16 software, Topo France map and Topo España v.3.0 vector map.
I chose the Etrex HCx GPS for three reasons

  1. I can download vector maps to it from my computer
  2. It has an internal barometer which measures heights more accurately than just relying on the satellites
  3. It has an in-built compass, which works even if there is no satellite reception.
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