Compact, handheld GPS units now provide extensive built-in maps. Photo by Bud Reiter

If there is a single phrase that invariably identifies an intrepid outdoorsman who strayed a bit too far from the beaten path, it would be "Where the heck am I?"

No one truly knows when that phrase was first uttered, but the chances are good it originated with someone wearing animal skins and carrying a stone-point spear. From that humble beginning, the refrain has achieved worldwide usage.

It is likely that Daniel Boone muttered it at least once, and was no doubt echoed by Lewis and Clark, Kit Carson, and an untold number of other early explorers. It is still in common usage today, and a phrase that tends to roll readily off the tongue when you think you know where your feet are planted at the moment, but have absolutely no idea of how those planted feet relate to the rest of the world at large.

Getting lost is not fun, and a number of tools have been developed to reduce the possibility. Accurate topographical maps were a start, and compact and reliable compasses added to their usefulness. If one could identify a couple of prominent terrain features, take a compass bearing on two or three, intersect those bearing lines on a map, a rough idea of one's location could be achieved and the proper bearing to the destination figured.

That worked on land, but did not serve sailors well, since recognizable landmarks are few and far between on the open ocean. They had to rely on bearings from stars and planets, which took a lot of training. The advent of the LORAN system was an improvement. Signal sending beacons on shore provided fixed reference points that could be intersected to determine an approximate location if the sailor had the proper receiver.

All of the above were improvements. But, it was not until the U.S. military decided to use modern satellite technology to provide a definitive answer to the question of "Where the heck am I?" that true precision became available.

The Global Positioning System utilizes an array of task-specific orbiting satellites -- each sending continuous signals back to earth -- that allow a GPS equipped user to determine with a tremendous degree of accuracy, exactly where the heck they are. If the receiver can locate a clear signal from just three of the orbiting birds a precise longitude and latitude in degrees, minutes, and seconds can be achieved.

Using those same divisions of latitude and longitude a user can not only figure out where he is, but also how to get to where he wants to be. If the GPS unit has the capability for the input the destination's numbers, which are easy to determine from the proper map, the satellites will then inform the user of how far that point is and what compass bearing to follow to reach it.

The biggest drawback to the early GPS units, however, was they could tell you where you were and could mark where you had been, but had limited ability to get you to where you wanted to go, unless you also had a quality map and a separate compass. On-screen maps could be downloaded into some of the better models, but that needed to be done in advance from a computer -- assuming the proper software was installed and the appropriate maps could be obtained. Only the most sophisticated military-grade units had those capabilities.