“Geocaching is “a high-tech treasure hunt for adults” – at least, that is the most succinct explanation enthusiasts can offer. A striking mix of the latest network technologies, unregulated gaming and muddy-boots bushwalking, it’s an activity that didn’t exist nine years ago. Now there are about 1 million cachers who participate worldwide, an estimated 13,000 of them in Australia. More get hooked all the time.

“Cachers refer to the wider public – the uninitiated hordes ignorant of their secret missions – as “muggles”, after the non-magic folk in the Harry Potter books. A cache that has been disturbed or trashed is said to have been “muggled”.

“Science writer Darren Osborne, who has been geocaching since mid-2003, says: “When I started, it was very much a clandestine activity. There are a number of people who do like the secrecy of geocaching and want to keep it that way but as more and more people find out about it, it becomes a bit harder to retain that secret squirrel, Get Smart stuff.”

“It’s not really about the treasure hidden inside the caches – typically trinkets from $2 shops or small toys. It’s about finding it. Caches are not buried but they are concealed – in tree trunks, under benches, under stones, sometimes even in fence posts or landmarks.

[…]

“Geocaching was invented in May 2000, within days of the US Government switching off the security restrictions on global positioning systems that limited the accuracy of civilian receivers. A Portland computer consultant, Dave Ulmer, posted a message online that he had hidden a plastic bucket with software, videos, books, food, money and a slingshot in the woods near Portland, says the author of Geocaching For Dummies, Joel McNamara. “He used his GPS receiver to record the latitude and longitude and encouraged others to try to find it,” McNamara says.”

Adult Hide and Seek, The Sydney Morning Herald