Geocaching is a treasure hunt which brings families together

Tim Teahan was deep in the Malaysian jungle with his young son, Ringo. They had been hiking for three hours, stepping over millipedes, pausing periodically to remove hungry leeches from their skin. Their only companions were the monkeys looking down from the trees. Finally, they found the treasure they were seeking hidden behind a waterfall: a jar containing a notebook.

Teahan, a Hong Kong-based physical education teacher, and his two sons, Ringo, nine, and Anakin, 10, are keen geocachers. This means they are participants in an ongoing hi-tech treasure hunt that has spread across the world. The hunts have been made possible because GPS (global positioning system) devices have become increasingly accessible and sophisticated.

Geocaching began in the United States 12 years ago. Now there are enthusiasts in more than 200 countries. Players hide caches - most often sealed containers with notes or small trinkets and a notebook - in out-of-the-way places and then post the GPS co-ordinates online. There are sometimes cryptic or coded clues to help the search.

The pursuit has certainly exploded in popularity in Hong Kong. In 2008, there were only 99 caches in the city, and around 20 active participants. Today, a quick browse through the website shows hundreds of caches here. The Hong Kong geocaching group on Facebook lists 362 members.

To non-players, or muggles as they are known in geocaching circles, the quests may sound simple, even boring. But geocaching requires careful planning and combines outdoor adventure, exploration, and the thrill of the hunt. Youngsters love it, and because the activity gets kids outside with their families, parents do, too.