X marks the spot for one activity gaining popularity in KELOLAND. It's called geocaching. People use their GPS systems to find hidden treasures or "caches." And for fans of the game, the chase for treasure is just as good as finding it.

For Sioux Falls resident Dorin Hemmelman and his family, geocaching lets them explore their surroundings.

"It takes us to places we would've never known existed without actually chasing down the cache there," Hemmelman said.  "And a lot of times, they're just places right in our backyard."

The caches themselves aren't usually extravagant. Some are simply a scroll for people to sign, while others are larger toys and trinkets.

"It's never really high-dollar stuff," Hemmelman said.  "But when you have your family along, they think it's kind of cool to find that treasure trove."

Caches can be placed anywhere with the proper permission. Those who hide the treasures mark their GPS coordinates and upload them to the official geocaching Web site.  And those who are interested, seek them out.

Caches can be found among a stack of tall branches at Lewis & Clark Recreation Area in Yankton.  But treasures around the world are a little more difficult to find.

"There are some geocaches that are only available by scuba diving and some only available by mountain climbing," Outdoor Campus director Thea Miller Ryan said.  "And sometimes, the prizes that people hide in those are just a little bit nicer because it's really hard to get there."

Whether the caches are simple or elaborate, Ryan says geocaching allows anyone to pursue a modern-day treasure hunt.

"It's definitely interesting people who really love the treasure stories of their childhood," Ryan said.  "Stories about pirates and people who found hidden treasures. That really appeals to geocachers."

And for the Hemmelman family, the hunt for treasure will continue.

"It's all about the seek," Hemmelman said.  "And when you finally find it, that's cool, but then it's on to the next one."

The Outdoor Campus in Sioux Falls has events this summer for both beginners and experienced geocachers.

More information on geocaching at The Outdoor Campus.