Millions of people grab a GPS device in their spare time and hunt for treasures scattered around the globe in an activity called "geocaching."
Geocaching, which began in 2000, is a popular pastime -- it is estimated that there are more than 2.5 million geocaches across the world, and millions more people searching for them.
Participants often use sites like geocaching.com or opencaching.com or apps to determine the GPS-tagged stashes they will try to find. Then, using a GPS device or smartphone, they set off to to find the hidden geocache.
Often the search for a geocache involves trekking through the desert, into the mountains or somewhere else off the beaten path. However, there are items in secret spots in urban areas, as well.
Once a location is narrowed down, there might be an additional clue about the specific location, otherwise a little poking around will be required.
Typically, when the geocache is found there will be a logbook to sign and date. Sometimes there are trinkets inside and those who find the geocache are expected to take something and then leave something for the next people who find it. Either way, put the geocache back where it was found and you are now ready to find your next geocache.
