Geocaches

For the traditional geocache, a geocacher will place a waterproof container, containing a log book (with pen or pencil) and treasures, then note the cache's coordinates. These coordinates, along with other details of the location are posted online. Other geocachers obtain the coordinates from the Internet and, using handheld GPS receivers, seek out the cache. The finding geocachers record their exploits in the logbook. Geocachers are free to take objects from the cache in exchange for leaving something of similar or higher value, so there's treasure for the next person to find.

Typical cache treasures aren't high in intrinsic value. Aside from the logbook, common cache contents are Two dollar bills or other unusual coins or currency; small toys; ornamental buttons; and CDs or books. Also common are "hitchhikers" (also known as Travellers or Travel Bugs), which are objects moved from cache to cache, and whose travels may be logged online.

Geocaches can range in size from "microcaches," too small to hold anything more than a log book, to those placed in five-gallon buckets or even larger containers.

Variations of geocaches include:

• Moving/travelling cache: The finder logs the cache, trades trinkets, then hides the cache in a different place.
• Multi-cache: requires a visit to one or more intermediate points to determine the coordinates of the cache.
• Mystery/puzzle cache: Coordinates listed are not the coordinates for the cache, the seeker must solve a puzzle to find the actual coordinates.
• Event cache: a meeting for geocachers, found by date, hour and coordinates.
• Cache-In Trash-Out (CITO) Events: A variation on the event cache, where geocachers get together at a particular location and clean up the trash in the area.
• Webcam: a location with a public web cam. You must have someone watching the camera on a computer to "capture" your image.
• Virtual: a location to visit simply for what is already there. To prove you visited the site, you are generally required to either email the cache owner with information such as a date or a name on a plaque, or post a picture of yourself at the site with GPS receiver in hand.
• Letterbox hybrid: This is a hybrid between geocaching and the much older activity of letterboxing. In addition to a logbook and trade items, it contains a rubber stamp to stamp your log book. Letterboxers carry their own stamp with them, to stamp the letterbox's log book.
• Locationless or reverse cache: the opposite of a traditional cache, as the game is to find a specific type of object, like a one-room schoolhouse, then log its coordinates and post a picture holding your GPS in front of the cache site.
• Earthcache: A type of "cache-less cache" sponsored and approved by the Geological Society of America. The locations do not have items, but contain information about the geology, fossils and local environment.