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

Artist from Salem, Massachusetts describes her boxes.

Community with forums, searchable clues, trip planner, recording of finds, event listings, trackers, tutorials, photo galleries, and chat room.

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

Clues for boxes she planted in Washington and Massachusetts.

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

Chuck and Molly's letterboxes in Connecticut.

Official site supports letterboxing in publicly owned state forests. Includes clues and a map of letterbox sites in state forests.

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.