All modern GPS units offer altitude as part of its location data. However, depending on the unit, and for reasons that will take too long to explain here, altitude data aren’t as accurate as long/lat data. That’s why some units feature an altimeter.

Barometers are useful if you need them. I never needed one in the Sahara personally.

A built in digital compass is nice to have as a backup. However make sure that the unit is equipped with a real digital compass. Modern GPS units WITHOUT a compass will still give you a compass display while you’re moving since it tracks your movement and tell which way you’re heading. If you stand still and turn the unit around it won’t correct your heading. I hope I’m making myself clear here….

I would consider the mapping features essential only if you’re going to travel on-road in well developed areas like Europe and the US. Other than that, forget it. You can still store embassies waypoints on a regular GPS if you want to.

Ask yourself if you really need the barometer, altimeter or any other of those cool add-ons. I still use the basic Garmin II+ and I’m very happy with it. When I feel like going hi-tech for a while I hook up my laptop and display some topo maps.

In my opinion I would get 2 cheap units rather than one expensive one for fault tolerance’s sake.

Also make sure you write all your waypoints down in your notepad at regular intervals, twice a day if you’re going off-road. GPS units do fail and might reset its memory for no apparent reason. This is less of a problem with modern units but it still happens.

Hope this helps.

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A.B.

OasisPhoto.com – Images from the Magical Sahara.
ShortWheelbase.com – Jeep preparations.

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A.B.
OasisPhoto.com – Images from the Magical Sahara.