A location system using orbiting satellites originally developed by the United States military is now the main tool in a grown-up game of hide-and-seek.

Geocaching (geo-cashing) uses hand-held global positioning system (GPS) receivers to find hidden "treasure" hiding in trees, under rocks and along city streets throughout the world. About 4,023 such stashes exist within 100 miles of Prescott ­- including at least one site in downtown Prescott - with "cachers" adding more all the time.

GPS enthusiast Dave Ulmer created the game within days after the United States government flipped the switch on its worldwide global positioning system to let U.S. civilians with GPS receivers - and the rest of the world - get accurate readings. That was on May 2, 2000.

Until then, the U.S. military scrambled the signals to avoid putting pinpoint accuracy into the hands of possible enemies.

Today, thousands of people worldwide are geocachers,All participants need is a hand-held GPS system and a computer. By logging onto www.geocaching.com - or any other geocaching site ­- and becoming a member, people can enter a ZIP code and find the longitude and latitude of any site within 100 miles.

Organizers prefer not to publicize the exact locations of the sites in fear that someone might "muggle"

The geocaching community has adopted the Harry Potter term as a description of people who either do not understand or do not respect the sport of geocaching and destroy the sites.

Each site has a rating of the difficulty of finding it and according to the difficulty of the terrain.

Some sites have a name and some names are clues to help find the site, Sometimes the write-up about the site contains a hint and sometimes the hints are in code.
"That's what's so much fun is reading some of the logs that people place on the website,"

Every geocache "belongs" to someone who has the responsibility to maintain it,Each person who takes something from a site is supposed to leave something in return.
 

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