The Boston Globe reports a new variation on geocache called letterboxing.
The plan is to leave messages with clues to the next box in the woods.
If letterboxers find a box they leave behind written messages and, using artistically carved stamps, their own personal emblems. They also use a stamp provided in the box to mark the journals they carry, giving them a record of another successful quest.
Letterboxing traces its roots back 150 years. The legend, according to Letterboxing North America, is that in 1854 a gentleman simply left his calling card in a bottle by a remote pool on the moors of Dartmoor, in England. The calling card evolved into a unique signature stamp. Today there are thousands of letterboxes hidden in what is now Dartmoor National Park.
Enthusiasts trace the beginning of letterboxing in America to the publication of an article in Smithsonian magazine in 1998 about the hobby in England, but it started slowly in the United States and remains somewhat obscure.
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