GPS Units

GPS Units

GPS and use in the hills and mountains

GPS Units 

Using GPS in the Mountains

When GPS receivers first became available they were relatively expensive and quite basic, giving a six figure grid reference and limited storage of waypoints, which had to be added manually, and no facility to download data. The principle was that you could check your position to confirm your navigation. At the time there was concern that people would go into the hills without the required navigation skills and have an over-reliance on their GPS gizmo. I recall an annual report by a mountain rescue team, which harked the same doom a few years earlier when mobile phones started to become popular. Who would now argue that mobile phones are essential emergency devices when walking?

Let’s be clear though, a GPS unit in the hills, if used properly, could be a lifesaver. If you need to check your position, particularly if a wrong move would spell disaster, then using a GPS unit can only be a good thing. However, if you use a GPS receiver as your primary means of navigation, then the critics were right and you should spend some time learning the more traditional navigation techniques, as such techniques do not run out of batteries, break when dropped or otherwise malfunction when you need them most. Always take a map with you in the hills, even if you have a GPS receiver that has inbuilt mapping.

GPS units do of course have their place and the remaining sections on GPS will explain some of the information you need to know to get the best from your GPS receiver, and ensure that it works when you need it to.

GPS Unit Features

Modern GPS units have a whole host of features, and below is a summary of the more common ones.


A waypoint is a pre-walk input of a grid reference or set of co-ordinates which references a specific geographical location. Typically, waypoints would be entered for the ends of key legs of a walking route.


By entering a series of waypoints you can create a route. If you enter a route before your walk and keep it switched on during the walk, the GPS unit will display a time estimate for you to reach the next waypoint. This is a handy feature for the purposes of estimating time, but extreme care has to be taken to enter sensible waypoints of a route, taking into account topography (up/down hill) and more importantly any dangers along the way. 


If you keep the GPS unit switched on, it can be set to record take a store positional fixes as you walk. This feature is good if you ever need to back-track where you've walked, and some units have a 'reverse' or 'back-track' function. Read more about GPS tracking here.

Computer Connectivity

Having recorded a track, most units will allow you to connect to a computer and export the track as a GPX file, which can then be imported into a range of software and/or website mapping tools. Examples include Memory Map and Social Hiking

Base Mapping

All GPS units have the capability of displaying a grid reference and the basic units will show digital lines that represent either a route or track. As the price of units increases, so do the functions, and units that allow display of Ordnance Survey Maps are not uncommon. The benefit of displaying an OS map is that the unit will show on screen the exact position on a map, which is easier to understand that just a grid reference. A drawback is that there is the natural inclination to pay too much attention to the GPS unit map, rather than the traditional map that should also be carried.

Digital Compass

The direction heading can be displayed on screen, but is no substitute for carrying a proper base plate compass, which can be laid on a map and used to take bearings.

Proximity Alarms

The ability to have an alarm go off when you're close to a predefined waypoint.

Sunrise & Sunset Times

Properly plan your route in advance but knowing the sunrise & sunset times, and double check when out on the hill. Brilliant feature.



The featured image is one of the first UK GPS units from the mid 1990s. It's the Magellan GPS 2000 and cost about £200 at the time (approx £340 at today's prices). Functionality was primitive when compared to today's GPS units.