In the recent war in Iraq, Global Positioning System satellites guided coalition bombs to their targets and helped American troops on the ground keep track of friendly forces nearby. The Pentagon developed GPS technology during the Cold War, but now civilians are coming up with their own applications. Curt Nickisch reports from South Dakota on the growing popularity of Geocaching, a hi-tech scavenger hunt.
On a brush-covered slope overlooking the Missouri River, Gerry Pallesen is zeroing in on a stash of hidden objects by monitoring his handheld GPS receiver. Picking up signals from satellites orbiting far above him, the unit calculates his position on Earth within just a few meters. "North latitude is 49.746ş, the coordinates given were 49.748ş. West coordinates, I'm right exactly on there, so the base of this tree right here looks rather suspicious when there's a couple of sticks and a pile of grass," he says. "So that's got to be my cache located right there!"
Gerry Pallesen moves the camouflage aside to uncover the cache - that's cache as in supply, not money. It's one of several he'll need to locate to complete the scavenger hunt. This one's a watertight plastic container crammed with inexpensive knick-knacks. Mr. Pallesen takes a miniature flashlight and leaves a golf ball in return before covering the cache again. That's the etiquette. But for this retired small town postmaster, the real value lies in the adventure of seeking and finding. "I'm just inquisitive by nature, and I'm getting a lot of good exercise," he says. "I'm 73 and I need to get out and walk more. Doctor said taking my dog out on roller blades doesn't count, so I do this instead, all right?"
Mr. Pallesen is part of a rapidly growing community of enthusiasts, hiding caches and then posting their coordinates on the Internet. Some are easy to locate; others are stashed kilometers from a road, or even underwater. The website Geocaching.com keeps track of more than 50,000 caches in over 170 countries around the world. Website founder Jeremy Irish says with easy-to-use GPS receivers costing as little as $100, the hobby appeals to a wide spectrum of people. "They want to be explorers, everybody wants to be an explorer. And the idea of going Geocaching and exploring the outdoors and seeing it in a different light and experiencing or finding something, really plays on the explorer interest of an individual," he says.
However, like other explorations, Geocaching raises questions about whether its members will spoil what they encounter.
"We're not excited about Geocaching," says Scott Lopez, the chief ranger at Badlands National Park, which overlaps some of the Pine Ridge Indian Reservation in South Dakota. Placing caches is outlawed in national parks. Ranger Lopez says the hobby threatens their natural and cultural resources. "We ended up finding a geocache where some folks had come in and dug up a hole in the ground and put a box in the ground with all their trinkets in," he says. "Come to find out it was within 5 meters or so of an archeological site, which was the remnants of a teepee ring. And these are culturally sensitive areas for not only the national park but for the Oglala Sioux Tribe."
At Geocaching.com, Jeremy Irish says his website tells users to be responsible by learning the rules and asking permission before hiding a cache. He says some states actively court geocachers to use their public lands, and he hopes more government agencies will follow suit.
Meanwhile, the number of geocachers is growing, and they're constantly coming up with new ideas to make the game more interesting. Here in South Dakota, a few have been hiding caches along the route of the Lewis and Clark Expedition in advance of the bicentennial of the journey next year, allowing locals and tourists to follow the explorers' path in a new way.