Who knows what you will find when you step out on a geocaching adventure?
A cleverly hidden capsule … a cunningly devised puzzle … the love of your life?
Geocaching is a high-tech treasure hunt in which you use your smartphone or GPS device to find hidden "caches".
It has created a worldwide community of geocache hiders and finders, as some players hide small "treasures" in carefully recorded locations while others seek them out.
Jo Cox has been geocaching for about five years. She has found about 1,300 caches — and that's not all.
"Would you believe, I actually met my partner [Ross] through geocaching," she said.
"I was hiding [caches] in my local area and you start to get to know others in the community.
"We eventually met and became friends. Then we went along to a geocache mega festival and the magic happened there."
Ms Cox initially saw geocaching as something to keep her kids amused.
"They are primary school age and they are into games and treasure hunting.
"I downloaded the geocaching.com app for the kids. The first one we found was right in front of a church and a school. It was at the base of a tree. I'm not sure who was more excited to find it.
"Ross and I now do more geocaching together than we do with the kids."
Stash in a cache
While the method of finding each geocache is essentially similar, there is no set formula for what you may find within one.
Scrolls are common, as are notepads within a weatherproof box. Some caches invite you to exchange a small item like a plastic toy.
"We were surprised by the variety. We learned very quickly they are not all the same," Ms Cox said.
"Usually there will be something to sign and date, but some also have SWAG, which stands for 'stuff we all get'. The theory is you take a toy or trinket that's there and leave one of your own.
"The other thing you can find in a cache is what's called a travel bug, also called a TB or trackable."
Travel bugs are intended to travel from geocache to geocache, with each leg of its journey recorded on the app and website.
That way, you can keep track of where it has gone — you record it, take it and then leave it in another location.
"I called it Polly Panda, and it's been to Canada, New Zealand, Thailand, and right now it is in the Netherlands."
Hide …
The geocache game begins with the placement of a cache.
Science teacher Peter McClive, whose name within the game is Mister Doctor, has set up nearly 100 geocaches.
"You should start as a seeker. Before you do your first hide, it's recommended you find at least 20 first," he said.
"I remember when I found my first cache. It was a bit of a thrill to know they are there and that there is a person responsible for placing it. That's what encouraged me to do it."
Mr McClive tends to specialise on constructing field puzzles, also known as gadget caches.
These may be found the usual way, but if you wish to sign the logbook within, you must complete a puzzle to open the container.
Some of his puzzles are quite elaborate, in which you must enter a code, for example, to shift some magnets that will ultimately open a lock.
Once the cache is made, it is then placed. The hider records the location using their smartphone or GPS, and it is written up on a cache internet page with the appropriate instructions and hints.
It is then submitted for review for quality control and safety before going live on the app.
Seek …
Married couple Mary and David MacCarthy — caching name maccamob — know a thing or two about finding geocaches. They have found more than 43,800.
Their first geocache find was at the You Yangs south-west of Melbourne. Since then they have recorded a find in each Australian state and territory and in all 50 in the United States.
The MacCarthys use a GPS device rather than a smartphone, but their hunting usually begins on their home computer.
"We go on the internet to see what caches are around a certain area," Mr MacCarthy said.
Once you have the coordinates, it's time to start looking. The GPS will guide you close but it won't help you find the cache.
"You look for something that may look a little out of place," Ms MacCarthy said.
"You use your eyes and your brain. The more difficult, the longer it takes to find, the more satisfying."
Mostly a geocache is not so much a competition as it is a personal challenge between the hider and finder. That changes when a new geocache is placed.
"We call it an FTF," Jo Cox said. "FTF stands for 'first to find', and for some geocachers it's a big deal to be first.
"When there is a new geocache, you will find there will be many cachers trying to be the first."
