This is no ordinary art exhibition. What's on the walls at the Tomorrow Gallery in Manhattan isn't exactly the artwork. It's a clue. Collectors who want to be united with artist Brad Troemel's work have to search for it in Central Park using GPS coordinates first.

Tired of paying for studio space to house his artwork, Troemel decided to hide all of his pieces in the park instead. The idea came to him last summer while he was staying with his grandparents in Aurora, Illinois, and renting out his Brooklyn apartment on AirBnB to make ends meet. While there, he downloaded a geocaching app and discovered relics all over the woods that could only be found using exact GPS coordinates.

"Imagine if geocaching's use of GPS technology, concealment and open space were applied to passive storage rather than active treasure hunting," he wrote in a description of his "freecaching" process. "Space, it turns out, is everywhere."

So back in New York, Troemel double vacuum-sealed each piece in industrial plastic before stashing them in tree trunks, bushes, under the soil, near signs. Sounds incredibly risky, but he's confident that they'll be safer in those conditions than in a storage locker.

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Nature and discovery are recurring themes in Troemel's work. Previously he created plantable paper containing wildflower seeds and Beanie Babies, and made sculptural aluminum casts of inactive black ant mounds. Bright digital flower prints in frames slide up to reveal mushrooms embedded underneath.

Wooden blocks hang in grids on the walls at Tomorrow. Resembling a flattened Rubik's cube that hasn't been solved yet, one side of each block is painted in a color. Another side is printed with the certificate of authenticity. The third side, when all the blocks are oriented the same way, shows an image of the freecached artwork with the 18-digit GPS coordinates at the bottom. The GPS side is mostly turned away from the viewer — only a buyer gets them. The exhibition runs through January 8.

Two plastic-wrapped pieces weren't put up for sale, however. Troemel made the coordinates for them public at the exhibition's opening in early November, turning them into free art for whoever could find them first. That distinction went to Al Bedell and her friend Forest.

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After they plugged the coordinates into Google Maps, scavenging turned out to be more of a challenge than expected, Bedell told The Creators Project.

"We were on the Upper West Side near Strawberry Fields, and one of the pieces was hidden in one of those rock outcroppings in the park," she told the site. "I basically fell off a cliff in the name of geocaching for Brad's art." Bedell reached over the edge of a cliff to get the piece hidden in a crevice. The other was between two rocks, she said.

Bedell called the experience like Pokémon Go, but for real. As exciting as that was, I'm glad she didn't encounter any more danger and her knee didn't require stitches. I mean, this is Central Park. You really never know what you're going to find in there.

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