Redundancy in your personal hiker geographic information system

In 2017, crossing the Pyrenees on the Haute Route des Pyrenees, instead of carrying my printed maps for the entire journey with me the entire time, I opted to mail stashes of maps to myself in my food parcels. What could go wrong? Everything! A "stupid light" decision as Andrew Skurka would call it.

With the exception of one parcel that I received in Gavarnie, I could not collect any of the other parcels. It turns out the transfer of parcels from the German postal system to the French and Spanish one is not frictionless. An additional problem being that both the French and Spanish postal systems only hold General Delivery parcels for two weeks, and, in some cases, not necessarily exactly two weeks either. The "no food" part was not so bad, you can always cobble something together, but having no printed maps was no fun. At all.

By looking at larger scale maps posted in refuges whenever I could put a walking route together to the next refuge, but I also got lost badly once because I misremembered an important detail. Instead of getting off the Table des Trois Roix and heading to a stone shelter, I ended up walking around the mountain. By the time dead reckoning suggested that something was amiss night was falling. Not making the intended destination is not so bad. However, the area around the Table des Trois Roix is a karst area (limestone) and there was no water to be found for a day and a night. No food and nothing to drink. Not fun.

After I had found my way again a very nice Frenchman who gave me a ride let me have an old copy of a map of the area he kept in his car. This covered at least part of the next section and then I was lucky enough to meet again a Frenchman whom I first had met in La Pierre St. Martin at the refuge. He let me tag along with him to Gavarnie, where our ways separated and I received my maps and food as planned.

The following year, continuing the HRP, I decided to carry a phone with maps on it (Gaia GPS) and printed maps as a backup. I have a hard time lining up the big topological features in the landscape with the maps shown on the small phone screen, I do much better with printed sheets (11 x 17) of the same maps. I can't see myself hiking a trail, let alone a route, with just a map displayed on my phone and no larger scale image to look at.

The phone died at some point, but I had my printed maps and I was ok for most of the journey with the exception of one spot where a sort of optical illusion let me not appreciate the fact that what looked like a solid rock wall was in fact a set of two rockwalls with a gully in between. This gully was what I needed to walk up. In this situation having a working GPS would have allowed me to determine that I was maybe 100 m off from where I had estimated to be on the paper map. As a result I walked down the wrong watershed, which also featured a lake down below just as the watershed I should have gotten into. I had all reason to think I was going down the right trail. But I was not. This cost me a day as I only reluctantly returned to the pass from which I had come down, thinking that no new information would transpire if I did return and that I was likely missing something else. Eventually I returned to the pass since I could not convince myself that I had identified what else I was missing. Sitting up at the pass again and scratching my head as to what I needed to do, a change in light made it suddenly obvious that I was not staring at one wall, but at two stacked walls. Heading over there I found the narrow gully and I was off to the races.

During my Utah traverse I drowned and destroyed my phone while recharging it. But I carried printed backup maps. Then one day I needed to find a water source that I had confirmed with a ranger was running and that was shown on the map. However, this source was located deep in a canyon and I was not able to triangulate using the compass to larger features in the landscape as these were hidden behind the very close horizon of the canyon rim. For the Utah trip I had purchased an Inreach mini to give my home crew a GPS location every night so that they could monitor my progress and see that everything was ok. So I pulled out the Inreach mini and found out to my horror that the default way to display coordinates was the DDM format (degrees, decimal minutes) while my maps were printed using a UTM grid! There are online resources for the interconversion of the formats, but that's no help in the backcountry, whether your phone is alive or dead.

I had purchased the Inreach two days before I started my hike because you can't buy these things or have them shipped to where I live because nothing containing a lithium ion battery can go into the cargo hold of an airplane. So I was not really familiar with the Inreach, I had barely managed to get it set up for what I wanted to use it for. I had downloaded the user manual to my phone, but that was on the Fritz, so I was up the creek sans paddle.

So what do we learn from Thomas' misadventures?

1. Have printed maps and carry them with you, do not mail them to yourself, particularly when using unfamiliar postal systems. In the US mailing them to yourself, or, better, have someone mail them to you via the USPS as you progress along the route is not as big of a risk. USPS has a long hold time for General Delivery mail and you can check online whether the item has arrived at its intended destination.

2. Watch your phone like a hawk if you use it as your GPS on a hike. The combination of electronic maps and paper backup is much more powerful than either alone, even if the maps were generated by the same software.

3. Make sure that the way coordinates are displayed (UTM, DMM, DMS) on your Inreach or similar device is the same as the grid on your printed maps. If your phone GPS fails, for whatever reason, your Inreach can provide some of the function of the phone to get you located.

4. As I write this I find out that there are actually apps that you can have on your phone that will do the interconversion without requiring access to the internet. For example: Lat/Long & UTM Converter for Android or Coordinates-GPS Formatter on the Apple App store. I have not checked out either, but having something like this on your device is an easy way to increase redundancy in the way you access geographic information while in the backcountry.