One GPS to Rule Them All

A natural question for GPS users is, "Why can't I use one receiver for both trail and street navigation?" The short answer- you can. The long answer- you shouldn't, mostly.

There are more and more trail receivers that can be used for road navigation by buying optional street mapping. And many street GPS units can be used with optional topographic mapping. (By trail, I mean all backcountry uses, including hiking, backpacking, mountain biking, hunting, fishing, paddling, etc. By street, I'm referring to navigation in cities and on highways and roads.)

The problem is that the the two uses are completely different. On the road, a touchscreen GPS works best, preferably one that accepts voice commands. You need loud spoken directions including street names. You also need a large, bright screen. On the other hand, battery life is not important, because the unit will be powered from the vehicle except for short periods.

On the trail, you need a unit that can be operated easily with gloves. Rubberized buttons work much better than touchscreens in the field. With a little practice, you can operate the buttons by feel and location without looking at them. Though touchscreens do work with gloves, accuracy suffers and even without gloves you have to constantly look at the screen to operate it.

You also need long battery life and batteries that can be replaced in the field. Trail GPS units have replaceable batteries that last 12 to 25 hours, as opposed to 30 minutes to 4 hours for street receivers. And nearly all street receivers have internal, rechargeable batteries that can't be swapped out for a fresh set.

Few trail units have speakers, so they don't give spoken directions. (A few units have headphone jacks and can be connected to the AUX input on your car audio system or to a mount with a speaker.) Trail units have much smaller screens than street units. Trail receivers usually have screens measuring about 2.7 inches diagonally, while street receivers have 3.5 to 7-inch screens.

Many street GPS units come with lifetime map updates and free, ad-supported, lifetime traffic. Traffic information alone is a good reason to buy a street GPS because no trail units give traffic information. Street maps are usually an extra-cost option on trail GPS receivers and you will have to buy updated maps to keep your unit current.

That said, the best two choices for combined trail and street use are currently the DeLorme PN-60 series and the Garmin Montana series.

If you primary use is trail, check out the DeLorme PN-60 series. The PN-60 has a small screen but is light and compact, weighing 7.6 ounces with NiMH batteries. The unit comes with DeLorme Topo North America, which covers the US and Canada with vector topographic and street mapping at 1:24000 scale. Both trails and roads are routable, which means the unit will not only give you directions to the trailhead but also turn-by-turn trail directions to your favorite fishing lake. There is no headphone jack so you will have to look at the small screen while driving, although it does beep to warn you of upcoming turns. With this unit it is safest if a passenger does the navigating.

The Garmin Montana series is one of the heaviest and bulkiest receivers on the market at 10.2 ounces but it has a 4 inch touchscreen that automatically orients to to horizontal and vertical positions. A headphone jack allows to you connect it to your car stereo or an optional vehicle mount with speaker. For street use, you'll have to buy street maps for the area of interest, and then pay to update them. Traffic service is not available.

Here's the clincher- for the price of the Montana 600 you can buy an advanced street receiver such as the Garmin nuvi 2595LMT with lifetime maps and traffic, as well as a mapping trail receiver such as the Garmin Etrex 20 which accepts Garmin topo maps as well as custom maps and weighs just 5 ounces. And if you want, you can load topo maps on the nuvi and street maps on the Etrex.