While there are many hunt-based challenges to occupy would-be treasure seekers these days, perhaps none is so artistic as letterboxing. The steps to get into this activity are simple: As a letterboxer, you first choose a trail name that reflects your spirit, reveals your character, or simply sounds good. Then, you choose an image for yourself—something that you can (and here’s the artsy part) carve into a block of rubber and use as a stamp. This will be your personal sign. You’ll also need a logbook and writing implement, and some enthusiasts also recommend investing in a simple magnetic compass. Once christened and equipped, you can visit one of a couple letterboxing websites—such as Letterboxing North America or Atlas Quest—that compile lists of letterbox locations. These locations aren’t identified by addresses or coordinates, however. At least not in the traditional sense. Letterboxing focuses on clues, which can be general but straightforward directions, puzzling riddles, or something in between. Some clue-posters make use of traditional orienteering methods, including coordinates or degrees at which you’ll see certain landmarks if you’re standing in the right spot. Other posters create a narrative that sends you after the treasure by instructing you to count paces from a fencepost or boulder. Once you locate a box—typically a Tupperware-style container that can snap shut to protect contents from animals and the elements—you open it to find a mirror image of what you already have: a hand-carved stamp and a logbook. So you make an exchange. Press the letterbox’s stamp into your own logbook. This proves you’ve been to the site. Then, press your personal stamp into the letterbox’s logbook and sign your trail name, which is something like leaving your calling card. Subsequent successful searchers will see your symbol when they flip through the pages to find a free area to stamp their own visual identifier. Hidden logbooks soon become colorful albums that serve as a record of all the adventurers who solved the clues, and personal logbooks become journals that reveal everywhere an active detective has been. Letterboxing shares some common elements with geocaching, but don’t think that the former is a rip-off of the latter. According to enthusiasts, letterboxing began in England in the 1850s, so it has a 150-year-old historical base. What chaps across the pond call a “letterbox,” U.S. citizens refer to as a “mailbox.” Either way, the concept is the same: There is a point in space that serves as a location to both receive and send out messages, connecting people who want to communicate with each other in creative ways. And letterboxing certainly does attract creative people. Many fans pick up the hobby because they like the idea of making unique stamps. These are personal stamps that the treasure hunters use to identify themselves to others and/or stamps to be left behind, hidden in boxes. There’s something special about knowing that people far and wide might be carrying around a logbook that features ink in the shape of a design you created. Letterboxing also attracts people who are new to the idea of navigation challenges. The activity is ideal for kids, because while there are extreme boxes hidden at the ends of long hikes or even tucked among rocks that poke from the ocean like tiny islands, there are also boxes stashed in public urban areas, like parks and even businesses. A quick search of your zip code will reveal the rough locations of probably dozens of boxes, some of which might be a short drive, bike ride, or walk away. After finding a few boxes on your own, you may be inspired to join the community by making your own box, complete with a stamp and set of clues leading to it. Be careful. Letterboxing can be addicting.