On July 23, a 66-year-old woman from Tennessee, Geraldine Largay, was supposed to meet her husband at a point on the Appalachian Trail in Maine, and when she failed to make the rendezvous, he declared her missing. Largay was an experienced hiker and in good health, but she simply vanished. Despite an intensive search, which has just been scaled back, there is not a trace of her. Heart attack? Bear? Human monster? We don’t know and we may never know.

The most notable wilderness disappearance was that of Congressman Hale Boggs, whose plane vanished in a remote part of Alaska in 1972, resulting in the most sustained and intensive rescue search in U.S. history. Not a trace was found. The plane, Hale Boggs, and his fellow passengers simply ceased to exist.

The vast majority of people who become lost or otherwise get into trouble in the wilderness are found within three to four days. If it goes beyond that, the chances that they will be found alive grow rapidly smaller with each day.

Some people take consolation in the fact that they have developed “wilderness skills”–they can build a shelter from pine boughs, or start a fire with a bow drill after the matches run out, or catch fish with a safety pin and wood grubs. This is all well and good, but it’s not going to save your life. If you’re stuck in the wind and freezing rain, your pine-bough shelter is going to leak like a sieve. If you can find dry, hard wood, you can make a fire pretty quickly with a bow drill, but if the only wood at hand is wet and punky, it will take hours…if you can do it at all. If you can catch fish with a safety pin or snare rabbits, it will help a little, but not enough. You need a minimum of 2,500 calories a day if you are active in the outdoors, and you won’t get anywhere near this on dace and sculpins and the occasional rabbit.

As a result, you will experience catastrophic weight loss, become progressively weaker, and after three weeks your body will shut down.

In large chunks of the wilderness, there is simply not enough to eat that can sustain human life. Even for hunter/gatherers who are born to the life of the food-scrounger and skilled at it, the threat of starvation is always present.

Remember the Rule of Three:
You can go three minutes without air.

You can go three hours with your body’s core temperature below normal.

You can go three days without water.

You can go three weeks without food.

Break the Rule of Three and you will get your name in the paper.

If you’d like to stay out of trouble, carry good survival equipment and know how to use it. Don’t do dumb stuff. And remember that all smart, experienced outdoorsmen are afraid of the wilderness. Not just respectful; afraid. They know that sometimes, you simply vanish.