Letterboxing is an outdoor hobby that combines elements of treasure hunting and hiking. Participants hide and seek small, weatherproof containers, called letterboxes, which contain a logbook and a unique rubber stamp. The goal is to find these hidden boxes using clues and then stamp a personal logbook with the found stamp. To start letterboxing, individuals can search for clues online or in printed guides. Once they locate a letterbox, they sign the logbook and may leave their own stamp as a record of their find. This activity encourages exploration of nature and creativity in crafting clues and stamps.