Geodashing

Geocaching is an outdoor recreational activity, in which participants use a Global Positioning System (GPS) receiver or mobile device and other navigational techniques to hide and seek containers, called "geocaches" or "caches", at specific locations marked by coordinates all over the world. As of 2021 there were over a million active players in the United States.

Geocaching can be considered a Location-based game.

A typical cache is a small waterproof container containing a logbook and sometimes a pen or pencil. The geocacher signs the log with their established code name and dates it, in order to prove that they found the cache. After signing the log, the cache must be placed back exactly where the person found it. Larger containers such as plastic storage containers (Tupperware or similar) or ammo boxes can also contain items for trading, such as toys or trinkets, usually of more sentimental worth than financial. Geocaching shares many aspects with benchmarking, trigpointing, orienteering, treasure hunting, letterboxing, trail blazing, and Munzee.

History

Geocaching was originally similar to the game letterboxing (which originated in 1854), which uses clues and references to landmarks embedded in stories. Geocaching was conceived shortly after the removal of Selective Availability from the Global Positioning System on May 2, 2000 ( Blue Switch Day.), because the improved accuracy of the system allowed for a small container to be specifically placed and located.

The first documented placement of a GPS-located cache took place on May 3, 2000, by Dave Ulmer of Beavercreek, Oregon. The location was posted on the Usenet newsgroup sci.geo.satellite-nav at . Within three days, the cache had been found twice, first by Mike Teague. According to Dave Ulmer's message, this cache was a black plastic bucket that was partially buried and contained software, videos, books, money, a can of beans, and a slingshot. The geocache and most of its contents were eventually destroyed by a lawn mower; the can of beans was the only item salvaged and was turned into a trackable item called the "Original Can of Beans". Another geocache and plaque called the Original Stash Tribute Plaque now sit at the site.

Geocaching company Groundspeak allows extraterrestrial caches, e.g. the Moon or Mars, although presently, the website provides only earthbound coordinates. The first published extraterrestrial geocache was GC1BE91, which was on the International Space Station between 2008 and 2017. It used the Baikonur launch area in Kazakhstan as its position. The original cache contained a travel bug (the first geocaching trackable item in space), which stayed on the station until it was brought back to earth in 2013. Due to fire restrictions on board the station, the geocache contained no official paper logbook. As of February 2021, only one confirmed geocacher (in 2013) has actually found the geocache, although others have claimed to have found it providing varying amounts of evidence. To commemorate the occasion, Groundspeak allowed specialized geocaching events to be published across the world, allowing attendees to obtain a virtual souvenir on their profile.

The second geocaching trackable in space is TB5EFXK which is attached to the SHERLOC calibration target on board the Mars Perseverance Rover, which landed on Mars on 18 February 2021. Geocachers were given the opportunity to virtually discover the trackable after the WATSON camera sent back its first photographs of the calibration target that contained the tracking code number. The code is printed on a prototype helmet visor material that will be used to test how well it can withstand the Martian environment. This will help scientists in creating a viable Martian spacesuit for future crewed missions to Mars.

The activity was originally referred to as the ''GPS stash hunt'' or ''gpsstashing.'' This was changed shortly after the original hide when it was suggested in the gpsstash eGroup that "stash" could have negative connotations and the term ''geocaching'' was adopted.

Over time, a variety of different hide-and-seek-type activities have been created or abandoned, so that "geocaching" may now refer to hiding and seeking containers, or locations or information without containers.

An independent accounting of the early history documents several controversial actions taken by Jeremy Irish and Grounded, Inc., a predecessor to Groundspeak, to increase "commercialization and monopolistic control over the hobby". More recently, other similar hobbies such as Munzee have attracted some geocachers by rapidly adopting smart-phone technology, which has caused "some resistance from geocaching organizers about placing caches along with Munzees".

Geocaches

For the traditional geocache, a geocacher will place a waterproof container containing a log book (with pen and/or pencil) and trade items or trackables, then record the cache's coordinates. These coordinates, along with other details of the location, are posted on a listing site (see list of some sites below). Other geocachers obtain the coordinates from that listing site and seek out the cache using their handheld GPS receivers. The finding geocachers record their exploits in the logbook and online, but then must return the cache to the same coordinates so that other geocachers may find it. Geocachers are free to take objects (except the logbook, pencil, or stamp) from the cache in exchange for leaving something of similar or higher value.
Typical cache "treasures", also known in the geocaching world as SWAG (a backronym of "stuff we all get"), are not high in monetary value but may hold personal value to the finder. Aside from the logbook, common cache contents are unusual coins or currency, small toys, ornamental buttons, CDs, or books. Although not required, many geocachers decide to leave behind signature items, such as personal geocoins, pins, or craft items, to mark their presence at the cache location. Disposable cameras are popular as they allow for anyone who found the cache to take a picture which can be developed and uploaded to a Geocaching web site listed below. Also common are objects that are moved from cache to cache called "hitchhikers", such as Travel Bugs or geocoins, whose travels may be logged and followed online. Cachers who initially place a Travel Bug or geocoin(s) often assign specific goals for their trackable items. Examples of goals are to be placed in a certain cache a long distance from home, or to travel to a certain country, or to travel faster and farther than other hitchhikers in a race. Less common trends are site-specific information pages about the historic significance of the site, types of trees, birds in the area or other such information. Higher-value items are occasionally included in geocaches as a reward for the First to Find (called "FTF"), or in locations which are harder to reach.

Dangerous or illegal items, weapons, food, and drugs are not allowed and are specifically against the rules of most geocache listing sites.

If a geocache has been vandalized or stolen by a person who is not familiar with geocaching, it is said to have been "muggled". The term plays off the fact that those not familiar with geocaching are called muggles, a word borrowed from the ''Harry Potter'' series of books which were rising in popularity at the same time geocaching started.

Variations

Traditional geocaching gave birth to GeoCaching – an active urban game of the Encounter project. The game is quite similar to geocaching but has time limitations and hints.

Geocaches vary in size, difficulty, and location. Simple caches that are placed near a roadside are often called "drive-bys", "park 'n grabs" (PNGs), or "cache and dash". Geocaches may also be complex, involving lengthy searches, significant travel, or use of specialist equipment such as SCUBA diving, kayaking, or abseiling. Different geocaching websites list different variations per their own policies.

Container sizes range from "nanos", particularly magnetic nanos, which can be smaller than the tip of a finger and have only enough room to store the log sheet, to 20-liter (5 gallon) buckets or even larger containers, such as entire trucks. The most common cache containers in rural areas are lunch-box-sized plastic storage containers or surplus military ammunition cans. Ammo cans are considered the gold standard of containers because they are very sturdy, waterproof, animal- and fire-resistant, and relatively cheap, and have plenty of room for trade items. Smaller containers are more common in urban areas because they can be more easily hidden.

Geocache types

Over time many variations of geocaches have developed. Different platforms often have their own rules on which types are allowed or how they are classified. The following cache types are supported by both geocaching.com and opencaching.us unless stated otherwise.

A Traditional cache is the most common type and consists of a container with a logbook. Exact coordinates where the cache is located are given.

A Multi-cache consists of one or more stages, each of them containing the coordinates for the next one; the final stage contains a physical container with the logbook. An Offset cache is a multi-cache in which the initial coordinates are for a location containing information that encodes the final cache coordinates. An example would be to direct the finder to a plaque where the digits of a date on the plaque correspond to coordinates of the final cache.

Mystery or puzzle caches require one to discover information or solve a puzzle to find the cache. Some mystery caches provide a puzzle that must be solved to determine the physical cache location. Caches which do not fit into other categories are classified as mystery caches.

Challenge caches require a geocacher to complete a reasonably attainable geocaching-related task before being able to log the find. Examples include finding a number of caches that meet a category, completing a number of cache finds within a period of time, or finding a cache for every calendar day. On geocaching.com it is considered a subtype of the Mystery cache, while it is a type on its own on opencaching.us.

A Night cache is multi-stage and intended to be found at night by following a series of reflectors with a flashlight to the final cache location. Considered a variant of the Mystery cache on ''geocaching.com''.

A Chirp cache is a Garmin-created innovative advance on multi-caches using new wireless beacon technology. The Chirp stores hints, multicache coordinates, counts visitors and confirms the cache is nearby. These caches were fully supported at OpenCaching.com, but they caused considerable discussion and some controversy at Groundspeak, where they were given a new "attribute".

A Wherigo cache is a multi-stage cache hunt that uses a Wherigo "cartridge" to guide the player to find a physical cache sometime during cartridge play, usually at the end. Not all Wherigo cartridges incorporate geocaches into game play. Wherigo caches are unique to the geocaching.com website. Wherigo is a GPS location-aware software platform initially released in January 2008. Authors can develop self-enclosed story files (called "cartridges") that are read by the Wherigo player software, installed on either a GPS unit or smartphone. The player and story take advantage of the location information provided by the GPS to trigger in-game events, such as using a virtual object or interacting with characters. Completing an adventure can require reaching different locations and solving puzzles. Cartridges are coded in Lua. Lua may be used directly, but a builder application is usually used. The Wherigo site offers a builder application and a database of adventures free for download, though the builder has remained in its Alpha version since its last release in May 2008. The official player is only available for Pocket PC. A built-in player is available on Garmin Colorado and Oregon GPS models. The Wherigo Foundation was organized in December 2012. The group is composed of all Wherigo application developers who, up until that time, had been acting and developing separately. Their goal is to provide a consistent Wherigo experience across platforms, connect Wherigo applications via an API, and add modern features to the Wherigo platform. While Groundspeak is aware of this project, the company has yet to take a position.

A Letterbox cache or a Letterbox hybrid cache is a combination of a geocache and a letterbox in the same container. A letterbox has a rubber stamp and a logbook instead of tradable items. Letterboxers carry their own stamp with them, to stamp the letterbox's log book and inversely stamp their personal log book with the letterbox stamp. The hybrid cache contains the important materials for this and may or may not include trade items.

Moving or traveling caches are found at a listed set of coordinates. The finder hides the cache in a different location, and updates the listing, essentially becoming the hider, and the next finder continues the cycle. This cache type is supported at opencaching.us while it has been discontinued at geocaching.com.

Guest Book caches use guest books often found in museums, tourist information centers, etc. They are listed exclusively at opencaching.us.

The following cache types don't contain a physical logbook.

A BIT cache is a laminated card with a QR code, similar to Munzee. The BIT Cache also contains a URL and a password, for logging purposes. They are listed exclusively on opencaching.us.

Virtual caches are coordinates for a location which has some other described object. Validation for finding a virtual cache generally requires one to email the cache hider with information such as a date or a name on a plaque, or to post a picture of oneself at the site with GPS receiver in hand. New virtual caches are no longer allowed by Groundspeak,Geocache Listing Requirements / Guidelines
, retrieved January 12, 2013 but they remain supported by other sites. The Groundspeak website no longer lists new caches without a physical container, including virtual and webcam caches; however, older caches of these types have been grandfathered in (except for locationless or reverse, which are completely archived). On August 24, 2017, Groundspeak announced "Virtual Rewards", allowing 4000 new virtual caches to be placed during the following year. Earthcaches are one of the two exceptions to the no-container rule; they are caches in which players must answer geological questions to complete the cache. The other exception is for event caches; for an event to qualify, it must be specifically or mainly for geocachers, and must have a minimum duration dependent upon its category (CITO, regular, Mega, or Giga). Attendees of event caches can log that they 'attended', which will increment their number of found caches. Groundspeak created a waymarking website to handle all other non-physical caches.

EarthCache™ are virtual caches that are organized by the Geological Society of America, but are located in many countries. The cacher usually has to perform a task which teaches an educational lesson about the Earth science of the cache area. They are listed at geocaching.com.

Locationless or reverse caches are similar to a scavenger hunt. A description is given for something to find, such as a one-room schoolhouse, and the finder locates an example of this object. The finder records the location using their GPS receiver and often takes a picture at the location showing the named object and his or her GPS receiver. Typically others are not allowed to log that same location as a find.

Webcam caches are virtual caches whose coordinates have a public webcam. The finder is often required to capture their image from the webcam for verification of the find. New webcam caches are no longer allowed by Groundspeak, but they remain supported by opencaching.us.

Finally, a USB Cache or Dead Drop cache location has a USB flash drive embedded into walls or other structures. The cache is retrieved by connecting a device that has a USB port and can read standard text files. This type is available at opencaching.us.

There are a few kinds of events.

An Event Cache is a gathering organized and attended by geocachers. It is not a true cache, but is treated as such by geocaching platforms: it can be "found" upon attending the event.

Cache-In Trash-Out (CITO) Events are coordinated activities of trash pickup and other maintenance tasks (such as constructing footpaths, planting trees and removing invasive species) to improve the environment. CITO is an ongoing environmental initiative created by Groundspeak Inc. related to geocaching which encourages geocachers to clean up parks and other areas. This is done in two ways: specific events, traditionally around the time of Earth Day each year, in which groups go around picking up litter and maintaining the landscape while finding geocaches.

Finally, a GPS Adventures Maze Exhibit is an exhibit at various museums and science centers in which participants in the maze learn about geocaching. These "events" have their own cache type on geocaching.com and include many non-geocachers.

Geodashing

Geodashing is an outdoor sport in which teams of players use GPS receivers to find and visit randomly selected "dashpoints" (also called "waypoints") around the world and report what they find. The objective is to visit as many dashpoints as possible.

Unlike geocaching, nothing is to be left at the dashpoints; the sole objective is to visit them within the time limit.

The first game, organized by gpsgames.org, ran for two months (June and July 2001); each subsequent game has run for one month. Players are often encouraged to take pictures at the dashpoints and upload them to the site.

Stratocaching

Geocaching from space is a combination of flight to near space, the geocaching game, and a unique science experiment. The first Stratocaching event was held on 16 November 2013 in Prague and was successful. Ten caches and two "radioseeds" went up to into the stratosphere on a gondola called Dropion module carried by a high-altitude balloon. The caches and seeds then fell to earth for people to find.

Technology

Obtaining data

GPX files containing information such as a cache description and information about recent visitors to the cache are available from various listing sites. Geocachers may upload geocache data (also known as waypoints) from various websites in various formats, most commonly in file-type GPX, which uses XML. Some websites allow geocachers to search (build queries) for multiple caches within a geographic area based on criteria such as ZIP code or coordinates, downloading the results as an email attachment on a schedule. In recent years, Android and iPhone users can download apps such as GeoBeagle that allow them to use their 3G and GPS-enabled devices to actively search for and download new caches.

Converting and filtering data

A variety of geocaching applications are available for geocache data management, file-type translation, and personalization. Geocaching software can assign special icons or search (filter) for caches based on certain criteria (e.g. distance from an assigned point, difficulty, date last found).

Paperless geocaching means hunting a geocache without a physical printout of the cache description. Traditionally, this means that the seeker has an electronic means of viewing the cache information in the field, such as pre-downloading the information to a PDA or other electronic device. Various applications can directly upload and read GPX files without further conversion. Newer GPS devices released by Garmin, DeLorme, and Magellan have the ability to read GPX files directly, thus eliminating the need for a PDA. Other methods include viewing real-time information on a portable computer with internet access or with an Internet-enabled smart phone. The latest advancement of this practice involves installing dedicated applications on a smart phone with a built-in GPS receiver. Seekers can search for and download caches in their immediate vicinity directly to the application and use the on-board GPS receiver to find the cache.

A more controversial version of paperless caching involves mass-downloading only the coordinates and cache names (or waypoint IDs) for hundreds of caches into older receivers. This is a common practice of some cachers and has been used successfully for years. In many cases, however, the cache description and hint are never read by the seeker before hunting the cache. This means they are unaware of potential restrictions such as limited hunt times, park open/close times, off-limit areas, and suggested parking locations.

Mobile devices

The website geocaching.com now sells mobile applications which allow users to view caches through a variety of different devices. Currently, the Android, iPhone, and Windows Phone mobile platforms have applications in their respective stores. The apps also allow for a trial version with limited functionality. The site promotes mobile applications, and lists over two dozen applications (both mobile and browser/desktop based) that are using their proprietary