My wife and I, along with a friend of ours, were deep in the southeastern California desert in search of "Amos Cemetery," a small graveyard used by workers of the Southern Pacific Railroad in the late 1800s. We'd been told it was about 14 miles north of Glamis along the Ted Kipf Road.

So along we drove, stirring up dust and sand in our 4x4s. We finally had to stop and ask a group of dirt bikers, who told us we'd overshot it about a mile back. We went back and finally found it.

When I later tried to write directions to Amos Cemetery for Interment.net's cemetery transcription database at www.interment.net, I realized mine weren't any more helpful than those we'd originally been given. If I try to go back there 10 years from now, I may forget how to find it. That's when I decided to invest in a GPS device.

GPS, short for Global Positioning System, is a system of 24 satellites that orbit the earth, constantly measuring their positions. A GPS receiver communicates with the satellites to determine your current position. Boats and airplanes have used GPS devices for quite a while, but the technology has become so affordable that consumers—including the average family historian—can now buy them for personal use.

Searching out the cemetery
Like my desert adventure, many genealogists' cemetery research includes U-turns, tangled maps and stops for directions. It can be tough to find the old or abandoned cemeteries where many of our ancestors are buried. But GPS technology can help.

With a GPS device, you can stand in the middle of a cemetery and it will determine the latitude and longitude (and even altitude if it has enough satellites tracked). It can store your location in memory so you can refer to it again later. When you share your cemetery transcription with other researchers, the coordinates will give them a precise location. They can plug them into their own GPS receiver or use an online mapping service such as MapQuest.com, www.mapquest.com, to create a road map from the coordinates.

To find a cemetery, simply enter the coordinates into the GPS device and it will point the way. Basic models use a compass pointer to show you which way to go, the distance to your destination, your current traveling speed and estimated time of arrival. More advanced models include mapping data to provide a street map. Most GPS devices update their information every second.

So now it doesn't bother me too much if my driving directions are really bad—I can just note the coordinates. It's still wise to write a set of directions to at least identify a general region, but the coordinates pinpoint the exact location.

Finding your waypoint
All GPS devices have the ability to remember the locations you mark. My Garmin GPS 12 will store up to 500 locations (commonly referred to as "waypoints"). You can assign a short name and icon to each waypoint. And with mapping software for your PC, you can assemble a list of destinations to download to your GPS device.

Most GPS devices also let you create a "trip"—a series of destinations you want to visit. Once you've assembled the destinations for your trip, the device will tell you the distance (in miles) between each destination. The cheaper models measure distance as a straight line, which usually isn't practical for driving. But models with mapping data can plot a driving course and provide you with more accurate distance. You usually have to be within 500 miles of your destination to get directions.

You can expect to arrive pretty close to your destination. Latitude and longitude are measured by degrees, minutes and seconds; GPS receivers break down seconds into hundredths, which means you'd end up within 1 foot of the coordinates you entered. But a GPS won't actually be that accurate—many weather factors can offset the timing of the signals bouncing back and forth between the device and the satellites. Still, navigation experts claim that you can expect accuracy to within 15 to 40 feet.

Marking your territory
With the growing popularity of GPS devices, people have been compiling databases of locations and posting them online. For example, the US Geological Survey (USGS) has compiled a database of geographic names, along with their latitude and longitude coordinates, that can be really useful to genealogists. The USGS Geographic Names Information System (GNIS) mapping.usgs.gov/www/gnis/ covers dozens of "features," including cemeteries, streams, bridges and buildings. You can enter the coordinates into your GPS device and let it point the way.

There is a hitch: The USGS coordinates might not be definitive enough. They're accurate only up to about 100 feet because they don't break down the seconds into tenths or hundredths, as a GPS receiver does. And the information in the GNIS database is somewhat old; many newer, larger cemeteries aren't identified. But that shouldn't affect the accuracy of the coordinates.

You might want to create your own database of locations important in your family's history. You could mark coordinates for your great-grandfather's old house or the church where your grandparents got married. In fact, it might be a good idea just to mark the coordinates of old graveyards and structures before they get torn down or covered up by the sands of time. Even if old buildings remain standing, the roads leading to them may wither away, and later generations may have a tough time trying to follow the original directions.

I'd love to see a huge database of cemeteries—one that's more accurate than the USGS and that includes the tens of thousands of small graveyards that have been have left out. In fact, as a cemetery publisher, I'd like to see more cemetery transcribers invest in GPS devices and make a habit of marking coordinates. It's probably the best means we have for preserving the locations of abandoned graveyards.