Whether you are into hiking,  bicycling, hunting or boating, a portable handheld GPS can be a great asset in the outdoors.  For some people using GPS for navigation is an important part of the fun associated with an outdoor experience. Others may simply want a reliable substitute for paper topographic maps–or simply some insurance that they can find their way back home! Regardless of your outdoor interests, it’s not hard to find a good hiking GPS to match your needs and your budget.

We’ll begin with a broad overview of the kinds of devices available, and what features you may want to look for. An important distinction in handheld gps devices is between mapping and non-mapping units. Mapping GPS receivers display your position on a map that may include roads, trails and natural landmarks. Non-mapping devices provide directional information and let you plot your course with position-marking waypoints, and then retrace your route using a simple plotter screen but no underlying base map.

The simplest and least expensive non-mapping devices are personal trackers or locators, such as the Bushnell Backtrack series. Just set your starting point with one of these devices, and no matter how far or long you wander you will always know which way is home. However on the least expensive models, the number of waypoints that you can set is limited.  The next step up for non-mapping GPS takes you to the lower end of the Garmin eTrex and Geko series. These types of units can often be found for under $100, and support a broader array of routing options with 500 waypoints.

But what if you want to find your way to some desired destination, such as a remote campsite or mountain lake? For this you may want a GPS device with maps loaded that can show you where you are, relative to your destination, so that you can choose the best route. Obviously this will require good maps in addition to a GPS unit capable of displaying them. Both Garmin and National Geographic produce topographic maps for GPS devices, but make sure you actually have the level of detail you need before hitting the trail.

Mapping handheld GPS navigators begin with relatively simple units like the Garmin eTrex Legend and Vista. These units comes with (rather limited ) preloaded base maps and includes internal memory for uploading and storing additional maps.  Slightly higher-priced units like the Garmin eTrex Vista, Venture and Summit HC GPS navigators provide more memory–which you probably want if you plan to upload topographic maps–and some allow use of an SD card for loading and storing map data, including complicated routing information with large numbers of waypoints.

There are many variations among these models, but in general you can expect newer and more expensive units to come with better pre-loaded base maps and other improvements.  Any of the mid- to upper-range eTrex handhelds  are good if you want to load topographic map files individually, but don’t require huge amounts of data storage. These navigators have more sensitive receivers than baseline models, and come with a larger color screen. They also add additional features, including compass and altimeter, and often a rugged waterproof case for heavy outdoor use.

Hiking GPS units with pre-loaded topographic maps include the popular Garmin Oregon and Colorado series. A number of different versions are available, most with bright easy-to-read screens and 3D rendering of map data. Top of the line units add a range of other features including built-in cameras that automatically geo-tag photos. Another great option that comes with topographic maps is the Delorme Earthmate PN-40, or the newer and considerably more expensive PN-60.

Outdoor GPS users have dozens of options, and this review barely scratches the surface in terms of models and features available. Watch this site for individual hiking GPS reviews and ratings, and more detailed discussions of what features matter most in a handheld navigator.