A treasure hunt is on in East Bethel.

In welcoming geocachers to their city, officials hope that locals and visitors alike will discover East Bethel's true treasures: its parks and open spaces.

Geocachers use hand-held GPS devices to find caches of trinkets, hidden in camouflaged waterproof containers, usually on public land. When they find a treasure, they sign a logbook and choose from an assortment of mostly worthless trinkets -- say a bouncy ball, a small figurine or a baseball card. They leave behind an item of their own and replace the cache precisely where they found it.

During the past couple of years, City Council Member Heidi Moegerle has been intrigued by geocaching displays at the Minnesota State Fair.

She thought the hobby sounded like fun and could be put to practical use in East Bethel: "We have parks that are underutilized. We're trying to naturalize some of them, so they're more natural and less equipment-based. I said, 'This would just be perfect.' "

Moegerle spoke to Nate Ayshford, the city's public works manager, who happens to be a geocacher in his spare time. He took the idea and ran with it.

Rather than using city resources to hide and manage caches, he reached out to geocachers in the area, who agreed to add their coordinates to the city's registry and to add caches to parks that didn't already have them. City staff designed a brochure and posted the location codes on the city website.

"I thought it would be a good way to promote the parks, get people into the parks and get people out and active in our community," he said.

Moegerle said she hopes the activity will appeal to kids' sense of adventure.

"What a great idea, to present it as an outdoor treasure hunt," she said of Ayshford's approach. "I thought that is a very cool way of intriguing kids to get them outdoors to get the exercise they need."

For now, users will need to provide their own equipment. The city opted not to offer GPS units for check-out or rental, but didn't rule it out, Moegerle said. Ayshford noted that many smartphones can download applications for geocaching.

It's hard to say whether use is up since the city started promoting the activity in June. By its nature, geocaching is an underground kind of activity. Ayshford has offered a secret code that participants can piece together if they find all the caches. Code-crackers might get a trinket, or get their photos posted on the city website, he said.

As of last week, no one had come forward with a solution to the code.

Maria Elena Baca • 612-673-4409