More on Letterboxing: I first heard of Letterboxing from this article in my Father’s Smithsonian when I was in college. I seem to remember a much longer article. But briefly the history is, it started on the moors of Dartmoor somewhere around 1854 and people have been trading clues ever since. This article is what inspired Letterboxing in North America to be set up. Here is a little more on the history.