Article describing the basics and the factors that motivate people to start letterboxing.

Artist from Salem, Massachusetts describes her boxes.

Trip planning portal offers clue search by country as well as tutorials and premium members services.

Introduction, photographs of personal stamps, and clues for boxes planted in southwest British Columbia.

Clues for boxes she planted in Washington and Massachusetts.

Offering clues for letterboxes in the Syracuse, New York area.

Search for boxes in Long Beach, San Bernardino and Lake Arrowhead, California.

Chuck and Molly's letterboxes in Connecticut.

Introduction, tips and things to avoid, news, survey, and letterbox clues for the Dartmoor area.

Includes a forum, image gallery, map of the area, contact details, and the history of the activity.

Rubber stamp carver Mitch offers instructions on how to carve a stamp, and some examples.

Clues for boxes in Dartmoor and in the Netherlands. [English and Dutch]

Posts first finds submitted by new US letterboxers, organized by state.

Virtual letterbox clues lead visitors on an online hunt.

Weblog about his letterboxing hobby.

Feature story datelined Oakland, New Jersey. (June 14, 2002)

Clues to letterboxes he has placed, mostly in the Northwest US.

Introduction, contact details, and guidelines for letterboxing in the Dartmoor area.

Account first published as 'More Dartmoor Letterboxes' by Anne Swinscow in 1986.

Clues to quick and easy letterboxes to find while traveling on Route I-95, from Maine to Florida.

Clues for letterboxes located in Kansas.

Forum with clues and discussion topics. Includes helpful hints on methods and supplies.

Clues for Germany and other European countries. Includes photos and tips. [English, German]

Includes letterboxing basics and clues for Minnesota letterboxes.

US-based portal offering FAQ, links, forums, and a members-only section where clues can be submitted.