I’m a bit of a fanatic when it comes to outdoor GPS units and over the past 7 years I’ve owned nearly a dozen different models. I recently got a chance to use the Earthmate PN-40 from DeLorme and I have to say it’s one of my top 2 choices for camping and hiking.

The PN-40 is a color-screen, palm-sized GPS that uses 2-AA batteries. At first I was hoping for the unit to use a rechargeable battery but it turns out serious trekkers prefer the portability of replaceable batteries (no where to charge up on the trail!). The PN-40 has a rugged, rubberized case and it’s waterproof to IPX 7 standard meaning you can dunk it under 1 meter of water for 30 minutes and it will still work. The screen is readable in all but the brightest sunlight though some map images were harder to read than others (more on that later). The buttons on the PN-40 give you quick access to the most commonly used functions like marking waypoints and searching for points of interest but can be difficult to press with gloved hands.

Since the PN-40 was designed for hikers and bikers it comes with an incredible set of topographic maps via the DeLorme Topo USA software. I’ve been a fan of Topo USA for a while now - well before I tried the PN-40 - because it includes some of the clearest, most detailed outdoor maps available. You can transfer detailed topographic maps to the PN-40 to take on the trail, though unfortunately the process can be a bit tiresome using the slow serial-USB connection. The PN-40 comes with plenty of memory to fit detailed map coverage and you can add up to 32GB of additional memory though the SDHC slot.

Once you’ve loaded detailed maps on your PN-40 you can start using it as soon as you walk out your door thanks to its ability to provide driving directions. It won’t talk to you like your Nuvi or Tom Tom but it will help you navigate to an unfamiliar trailhead. Once you’re at the trailhead you can queue up a downloaded GPS track of the trail (Topo USA and the PN-40 support GPX formatted files) and follow it just as you would a road. The PN-40 even chirps like a bird when it’s time to turn - pretty outdoorsy if you ask me.

The PN-40 also has the (fairly) unique ability to view satellite and aerial imagery on the GPS itself. You’ll need to download the imagery before you head out and the imagery isn’t free (about $30 a year last I checked) but once you’ve loaded the images it’s like having Google Earth in the palm of your hand! Some satellite images were hard to read in direct sunlight and the images aren’t nearly as clear or detailed as some online services like Google Maps. Satellite images can certainly come in handy but at times I at times felt like it ruined some of the suspense and adventure of hiking. Instead of being surprised to find that the top of the mountain is bald, now I can see it before I’m out of the trees…

Of course the PN-40 also includes all the functions you’ve come to expect from an outdoor GPS - time, distance, speed, etc. but it also includes some helpful functions like a digital compass, barometric altimeter, and fishing and hunting functions. If you’re looking for a good all-around GPS to use in the great outdoors and you’re tired of paying for extras like detailed maps (ahem, Garmin) the DeLorme Earthmate PN-40 is a good choice that won’t break the bank. Just don’t forget to bring extra batteries