What is Letterboxing?
Letterboxing is an intriguing mix of treasure hunting, art, navigation, and exploring interesting, scenic, and sometimes remote places. It takes the ancient custom of placing a rock on a cairn upon reaching the summit of a mountain to an artform. It started when a gentleman simply left his calling card in a bottle by a remote pool on the moors of Dartmoor, in England.
Here's the basic idea: Someone hides a waterproof box somewhere (in a beautiful, interesting, or remote location) containing at least a logbook and a carved rubber stamp, and perhaps other goodies. The hider then usually writes directions to the box (called "clues" or "the map"), which can be straightforward, cryptic, or any degree in between. Often the clues involve map coordinates or compass bearings from landmarks, but they don't have to. Selecting a location and writing the clues is one aspect of the art.
Once the clues are written, hunters in possession of the clues attempt to find the box. In addition to the clue and any maps or tools needed to solve it, the hunter should carry at least a pencil, his personal rubber stamp, an inkpad, and his personal logbook. When the hunter successfully deciphers the clue and finds the box, he stamps the logbook in the box with his personal stamp, and stamps his personal logbook with the box's stamp. The box's logbook keeps a record of all its visitors, and the hunters keep a record of all the boxes they have found, in their personal logbooks.
Where are the Letterboxes Hidden?
Virtually all letterboxes are in England, and in particular, in Dartmoor National Park, in Devon, with estimates ranging from 10 to 40 thousand, depending on who you ask. I have heard of boxes in elsewhere in continental Europe, Africa, and Asia, and some in North America that predate the "modern", (or "post-Smithsonian") era of American letterboxing. As for North America in the post-Smithsonian era (Apr '98), there are approximately 5000 boxes scattered about the country, and the number is growing fast. This FAQ is geared towards letterboxing in the USA; many details are different for Dartmoor letterboxing.
What Do I Need to Hunt for Letterboxes?
At the very minimum you will need the clues. You should also have a personal stamp, inkpad, personal logbook, and a pencil (for writing in the box's logbook, if you want). Depending on the clue, you may also need a compass, map, or other tools. For my personal logbook, I use a hardbound unruled art sketchbook. I like the unruled paper because the stamp images look better. I also use a dye-based acid free ink; inkpads can be gotten at many art stores (preferred) or some discount department stores. Some people use multiple ink pads for a multi-colored effect, and some people use pigment-based ink. I prefer the dye-based as it dries faster and seems less messy, but this is all up to personal preference.