Finding the Trailhead with GPS

Navigating to a trailhead with GPS is not as simple as it sounds because most street GPS receivers don't have trailheads in their points-of-interest (POI) databases, unless the trailhead is located at a park or other general attraction. And street GPS mapping, while remarkably good for highways, county roads, and city streets is often poor for back roads, especially in the western U.S. And finally, when street mapping does show back roads, it often doesn't distinguish between maintained, gravel dirt roads that are passable to most cars and unmaintained roads that often need a high-clearance or four-wheel drive vehicle to travel. Trail GPS units don't do road navigation unless you buy optional street maps, and then you still have the limitations of street mapping.

The solution to this problem involves a bit of planning at home before trying to find a backcountry trailhead at the start of your wilderness adventure. Just look at it as an extension of the planning for the wilderness part of the trip, where you're traveling on foot, by paddle, or other self-propelled means. The secret is to use a variety of resources to solve the problems:

• Locating the coordinates of the trailhead
• Finding the best route to the trailhead
• Setting up your GPS receiver to navigate the route to the trailhead
• Determining if you need a four-wheel-drive vehicle

Unless you're planning to depart cross-country from an unusual starting point, these days you can find descriptions of trailheads and driving directions in guidebooks. Newer guidebooks often publish the GPS coordinates, so all you have to do is type them into your GPS receiver and save the trailhead as a named waypoint. If the coordinates aren't published, use the guidebook description and an online or computer topo map or Google Earth to locate the trailhead and get the coordinates.

If you have a guidebook description of the route, you can follow along on a topo map and mark GPS waypoints at critical intersections. With a trail GPS, you can create a route and download that to your receiver before the trip. It is very helpful to have detailed topo maps of the approach route in your GPS, and you probably already have such maps loaded for the wilderness part of the trip. The guidebook should also tell you if you need a four-wheel-drive vehicle to reach the trailhead.

You can use a street GPS receiver to create waypoints and a route to the trailhead, but most street units won't download waypoints and routes directly from a computer mapping application. You may be able to save the route as a GPX file and transfer that to the street GPS via USB cable. This is worth the effort because of the road routing capability of street GPS receivers.

 If you don't have a guidebook description of the trailhead, then you'll have to work a little harder. You'll need to locate the trailhead on a topo map and then work out the best roads to reach that trailhead. Use caution with U.\SGS topo maps- they are often out of date and don't show changes to roads (although they are the most accurate maps for natural features such as terrain.) Often, you can get a road map from the land management agency in charge of the area that is much more up-to-date on the road system. Privately-produced printed recreation maps and online or computer-based maps are often the most current road maps. And Google Earth is a valuable resource, especially in desert areas where you can often get a good look at roads. Even in forested areas, you can at least tell if a road is likely to be maintained- if the road shows in a cut through the forest, it is wider and therefor more likely to be paved or at least graveled.

Whatever you do, don't blindly charge off onto backcountry roads trusting your street GPS receiver. That's a good way to find yourself at a dead end, or worse, with a broken or stuck vehicle.