KENNESAW, Ga. -- Anna Calcaterra is a modern-day pirate who spends her free time searching for buried treasure.
"This is the fun part," she said as she poked at a pile of pine needles to find a hidden ammo can. "That's exactly what it is. It's buried treasure."
PHOTO GALLERY | Geocaching lets you find hidden treasure
WATCH | Learn the secrets of Geocaching
She's hooked on geocaching, which is defined as the outdoor sport or game of searching for hidden objects by using the Global Positioning System.
"It has seriously brought me to places that I would have never been before, patches of woods or waterfalls that you would never know exist," Anna said.
She relied on paper maps when she started almost five years ago, but smart phones have changed everything.
There are several apps that can track your location and help you find caches almost anywhere.
"There are almost two million in the world. Most of them are in the U.S." she added.
They're put in place by other geocachers. Anna hid one geocache inside a pine cone in some woods off Barrett Parkway in Kennesaw.
"It's a real pine cone with a hole drilled in it," she explained.
Inside any cache, you'll find a paper log. You sign it, date it, then put it back exactly the way you found it.
Bigger caches also include toys or prizes. which one reason Anna often takes her children along for the hunt.
If you take something out, you're supposed to leave something else behind. Anna calls it "swag."
Anna has found more than 8,000 caches, but she'll never forget her first.
"It's called drive-thru cemetery," she said. "I came out five times. It took five trips to find it, so this is my favorite."
The name gives you a clue to the location. It's hidden behind a fake electrical plate that sticks to a cemetery gate with a magnet.
Anna took 11Alive's Jennifer Leslie to another one called "no trucks."
"So we'll start looking all around the sign?" Jennifer asked.
"It is hidden up in there, and a lot of times you find it by feel," she said.
It was a nano cache, a tiny magnetic container with a name log inside.
"It can be the easiest cache or the hardest cache. It doesn't matter," Anna said. "It's just a rush. I can't explain it. It's just, it's an adrenaline rush."
How to get started:
1) Register at www.geocaching.com.
2) Download a geocaching app. Anna uses c:geo on her Android. The official geocaching app costs $9.99 for iPhones. You can find other apps, too.
3) Use your phone to search for geocaches in your neighborhood. You can also search when you're on vacation or taking a road trip.
4) If you find a geocache, sign and date the log. Put it back exactly the way you found it.
5) If the geocache includes prizes, take some and put something else back. Don't leave valuables or money, unless it's change.
MORE ONE TANK TRIPS
* Gibbs Gardens
* Red Apple Barn
* Southern Estate Alpacas
* Tallulah Falls
* Hike Inn
* Camp Toccoa at Currahee
* Callaway Gardens
* Blue Ridge
* Pine Mountain Gold Museum
* Ga. Aquarium Sea Otter Encounter
* River City Rush
* Historic Banning Mills
* Consolidated Mine