In this page, I've pulled together some of the more commonly asked questions about geocaching and the gear / effort involved in the sport. Some of this material comes from the C.A.C.H.E. FAQ list, other material comes from the Geocaching.com FAQ list, some from "How Stuff Works," and the rest of it I wrote myself. Since the material here is a hodgepodge of text, copyright for this material resides with the original various authors.
The Geocaching.com site also has a pretty good glossary of geocaching terms, and Navicache has its own FAQ list.
What is Geocaching?
Geocaching (pronounced geo-cashing) is a relatively young outdoor sport -- a search for waterproof containers full of goodies of some sort or other. The containers, called "caches", are placed anywhere in the world and their exact geographic coordinates are published on the internet. Other participants obtain the coordinates and other information from the internet and, using handheld GPS receivers, seek out the caches, hoping to write of their exploits in a the caches' logbooks. Geocachers are free to take objects from the cache, in exchange for leaving something in return, so there's always a "treasure" for the next person to find. Typical cache treasures aren't especially high in intrinsic value, but often make interesting souvenirs: unusual coins or currency, kids' toys from fast-food restaurants, ornamental buttons, and other simple trinkets.
What is the history of Geocaching?
Geocaching is based on the use of hand-held
GPS receivers. The GPS system has been used for years by
civilians, who can use the GPS's
Standard Positioning Service worldwide free of charge. In
the past, though, the civilian signal was intentionally
degraded (with only about 100 meter / yard accuracy). A
more accurate Precise Positioning Service was available
only to the United States military and select other (mostly
government) users. But on May 1, 2000, U.S. President Bill
Clinton decreed that this "Selective Availability"
(degradation of the civilian signal) would be turned off.
With the stroke of a pen, all users could then enjoy nearly
the same level of access, allowing position determination
within 20 meters.
The first cache was placed by Dave Ulmer near Portland, Oregon just a few days later on May 3rd, 2000. Three days after this, two people who had read about the cache on the sci.geo.satellite-nav newsgroup found the cache and entered their names in its log -- and geocaching was born!
How much does it cost to
Geocache?
The activity of Geocaching itself is completely
free. You will need a GPS
receiver, but you can rent one for a while if you'd
like to try Geocaching out before buying one.
GPS receivers can range in price from $100 to $1000 depending on the capabilities you are looking for. You can usually find them at boat supply store and larger camping stores, as well as online through Amazon.com and camping supply companies. Best of all, some outfitters (REI in particular) rent GPS receivers -- so you can try several models before you buy.
Who goes Geocaching?
Anybody who enjoys the outdoors and looking for
hidden treasure goes geocaching! You'll run across families
with kids, people looking for something to do while walking
their dog, and solo geocachers of a variety of ages.
Most cache listings do have a difficulty rating (generally, separate ratings for the cache difficulty and cache terrain difficulty) associated with them so if you're bringing small children or your grandmother with you, you might want to pick a cache on easier terrain, near a parking lot. If mobility isn't an issue, you can find more challenging caches that require technical climbing gear, and even underwater caches (SCUBA gear mandatory)!
What is GPS?
GPS stands for "Global Positioning System" (the
US military refers to it as NAVSTAR), a
satellite navigation system used for determining
one's precise location and providing a highly accurate time
reference almost anywhere on Earth. GPS is based on a
constellation of 27 Earth-orbiting satellites (24 in
operation and three extras for when one fails). The
satellites carry atomic clocks and constantly broadcast the
precise time according to their own clock, along with
administrative information including the orbital elements
of their own motion, as determined by a set of ground-based
observatories. The satellites' orbits are arranged such
that at any time, anywhere on Earth, there are at least
four satellites "visible" in the sky.
GPS receivers can then triangulate on these signals and determine their location on the Earth's surface.
See also the Wikipedia article on GPS, Trimble's tutorial "All About GPS," and this good writeup on the history of GPS and its uses here.
How does GPS work?
A GPS receiver's job
is to locate four or more of the GPS satellites, figure out the distance
to each, and use this information to deduce its own
location. This operation is based on a mathematical
principle called trilateration.
For details on this process, see the "How Stuff Works" article on "How GPS Receivers Work."
What is a GPSr?
GPSr is shorthand for GPS receiver. The most essential
function of a GPS receiver is to
pick up the transmissions of at least four GPS satellites in order to figure out
the receiver's position on Earth -- latitude, longitude and
altitude.
By inputting a desired destination's location into your GPS receiver, you enable it to do navigation for you (i.e., compute the distance and bearing to the destination from your current location). If you leave the receiver on as you walk, it can calculate how your location is changing. With this information and its built-in clock, the receiver can also compute a variety of useful data for you:
ï How far you've traveledï How long you've been traveling
ï Your current speed
ï Your average speed
ï The estimated time of arrival at your destination if you maintain your current speed
Basic (black & white display, no capability for stored maps) GPS receivers are available for well under $100.
To make navigation more user-friendly, many receivers can display their position on maps stored in their memory. Some receivers let you download detailed maps into memory or supply detailed maps with plug-in map cartridges. A mapping GPS receiver will not only place you on a map at any particular location, but will also trace your path across a map as you move. Receivers with map capability start at about $150
The price for a GPS receiver climbs (predictably) with added features. Higher-end units provide built-in electronic compasses, altimeters, color screens, even voice navigation (but they're more expensive, larger, and have shorter battery lifetimes than more basic units).
What is a cache?
In its broadest dictionary sense, a cache (from
the French verb "cacher," to hide) is a hiding
place, for concealing and preserving provisions. As for
geocaching, our caches are (generally) small, waterproof
containers with some contents of interest. At the very
least, this means a log to sign; most caches, though,
contain at least a modest selection of trinkets to trade
(but never ever food).
- Traditional - A physical container of a size in which
trinkets can be placed. These are usually military
surplus ammo cans or Tupperware®/Rubbermaid® containers,
and they are usually very well camouflaged.
- Micro - Usually a 35mm film canister or Altoids tin,
but can be anything small and fairly robust.
Microcaches only have space
for a log, and occasionally very small items such as
coins. Ultra micros are now appearing on the scene as
well. If only due to their size, all of these can be
exceptionally difficult to find.
- Virtual - Involving no physical container, virtual
caches are usually
historical sites, campsites with great views, interesting
locations, construction sites, etc. In most cases the
"hider" will request some type of information found at
the site be e-mailed to them to claim the find.
- Locationless (a.k.a., reverse) - To log a
locationless cache, you must
find (where-ever it may be) the item the "hider" is
looking for and log its coordinates. Often you must take
a photo of the item, including your GPSr, and upload it to the cache page to log the find. The most
famous locationless cache is a yellow jeep. There is a
fantastic list of active locationless caches here, courtesy of BeachBuddies.
- Multi - Multicaches
usually consist of a series of microcaches containing
coordinates for the next step or a traditional cache.
Usually, there is a puzzle to solve ,where information
gathered through your travels from one step to the next
are used to determine the final coordinates.
Multicaches are becoming
extremely popular lately.
- Offset - A variant of a multicache in which the posted
coordinates take you to some location; you must then
continue on using instructions, a map, and compass to
find the final cache
container.
- Event - Event "caches"
are get-togethers of some kind (club meetings,
get-togethers to help clean up parks, etc.). You claim
your "find" by showing up to the event.
- Mystery (puzzle) - A grab bag of cache types, a mystery cache can involve puzzles or mathematical problems that must be solved to determine the coordinates of the physical cache. Here the posted coordinates are for some nearby point (often a parking lot).
I'd also recommend you check out Geocaching.com's writeup on cache types here.
What's in a typical cache?
You could find almost anything in a cache, depending on its size.
A logbook should included in all but the smallest caches. The logbook contains information from the founder of the cache and notes from the cache's visitors. The logbook can also contain much valuable, rewarding, and entertaining information. A logbook might contain information about nearby attractions, coordinates to unpublished caches, and even jokes (or poems!) written by visitors. If you get some information from a logbook you should give some back. At the very least you can leave the date and time you visited the cache.
Larger caches will contain a logbook and some number of more or less valuable trinkets for trade -- small toys, books, LEGO bricks, stuffed animals, music CDs, CD-ROMS, tapes, etc. These items turn the cache into a true treasure hunt., since you never know what the founder or other visitors of the cache may have left there for you to enjoy. Remember, if you take something, its only fair for you to leave something in return.
Some caches contain a disposable camera. This isn't a goodie to be taken though; just take a picture of yourself and tell the cache owner if you snap the last photo. The cache owner can then recover the camera, develop the film, and put your smiling mug on their web page along with all the other visitors to the cache.
Any water-sensitive items in a cache should be individually packaged in a clear zipped plastic bag to protect them (caches do leak on occasion).
Is there anything that should
never be in a cache?
Whole families go geocaching together so items
should be safe and legal for all. No alcohol, drugs,
explosives, knives (not even pocket knives), alcohol, porn,
etc. Again, remember that all ages of people hide and seek
caches -- just use a little
common sense.
Food items are ALWAYS a BAD IDEA. Animals have better noses than humans, and in some cases caches have been chewed through and destroyed because of food items in a cache. Please do not put food in a cache.
How long do caches exist?
It all depends on the location of the
cache and its impact on the
environment and the surrounding areas. Caches could be permanent, or
temporary. It's up to the cache owner to periodically inspect
the cache and the area to ensure that impact is minimal, if
not nonexistant. When you find a cache, it's always a good
idea to let the cache owner know the condition as well --
particularly if the cache is missing / defaced.
How do I play the game(s)?
Geocaching is a relatively new pastime, so the
basic rules are very simple:
- Find a cache
- Take something from the cache
- Leave something in the cache
- Write about it in the logbook
The catch is that getting there is half the fun. Knowing that a cache is, for example, 11.2 miles northwest of you doesn't do you much good if there's an impassible mountain range, a lake, or something else in your way. You need to find your way around (preferably in a low-impact way). There's also the challenge of finding a container that has been deliberately concealed (and likely well camoflaged).
As geocaching grows as an activity, more attention is being paid to the impacts of geocaching, and of geocaching etiquette. Bert Carter provides an excellent writeup on etiquette in a "Today's Cacher" magazine editorial (mirrored here if it drops off the "Today's Cacher" site).
How do I find a cache?
You don't need to know all the technical
background behind GPS to play
the game. All you need to do is be able to enter what is
called a "waypoint" where the geocache is hidden. Once you
select a cache and enter its
coordinates into a GPS
receiver, the receiver can tell you how far away the
cache is and in what direction
it lies. Then you need basic hiking and map reading skills
to get you there safely.
In most cases, your trusty GPS receiver will get you within 20 feet of the cache (it'll generally tell you what the accuracy of its position is in real time). Once you get this close, you'll have to look around (using any hints from the cache's internet listing) to see where it's hidden.
Unless there's a note in the cache containing instructions on moving it to a new location, please don't move the cache! Responsible cache owners check on their caches occasionally and would be alarmed to find theirs missing. Do, though, re-hide the cache as well as you found it (so subsequent cache hunters can experience the same "thrill of the hunt").
The Geocaching.com site has some good tips on finding caches here.
How do I hide a cache?
First off, before you ever hide a new cache of
your own, it's generally agreed that you should have found
at least a dozen existing caches. This'll give you a good feel
for what works and what doesn't (both in terms of location,
as well as the hide techniques used). Once you have some
caches under your belt, here's
what you'll need to do:
- Survey sites -- find some good prospective cache sites. Sites shouldn't require
any digging or damage to vegetation, and please avoid
sites in particularly fragile areas. For sites in heavily
used areas (urban parks and open space, etc.) attempt to
pick sites very near existing trails. Since your cache may eventually see a fairly
large number of visitors, try to think of the damage that
cache hunters may
potentially cause in their searching.
- Ask permission -- always, ALWAYS ask
permission before placing a cache. In the case of private
property, ask the land owner. In the case of public
property, ask the responsible land manager (park manager,
open space office, etc.). In the case of wilderness
areas, you'll want (and sometimes need) to get permission
IN WRITING. I'm compiling a list of regulations on caching in various
Colorado public lands -- this should speed this step
for you.
- Select a container, and prepare the cache. The container should be able
to tolerate the environment it'll be exposed to, and
ideally water resistant if not waterproof. Make sure to
mark the container so that anybody inadvertently
stumbling across it will be able to tell what it is and
not get too concerned (post-9/11, this is increasingly
important). Include a note inside the cache to (again) let inadvertent
finders know about the cache
and geocaching.
- Place the cache.
Camoflage it with locally available material (loose bark,
dead twigs, etc), taking care not to damage vegetation or
dig holes. Take the best fix on it that you can with your
GPS receiver.
- Report your cache to a
geocaching website -- either Geocaching.com or Navicache (preferably both). The
site(s) will go through an approval process, you may /
may not have to tweak things a bit, then your cache is listed, and you're in
the game! Note that cache
approvals are performed by volunteers, please allow a
few days for any cache
you submit to be approved or rejected.
- Once your cache has been approved, make sure to do periodic maintenance (i.e., every month or so drop by to inspect the cache's condition). If the container is damaged, you'll want to replace it. If the cache's surroundings are experiencing visible damage due to cache hunting traffic, you'd be well advised to move it to a more robust location. As the cache owner, you are personally responsible for the upkeep of the cache, as well as for any damage to its surroundings.
The Geocaching.com site has a nice writeup on cache hiding as well.
Are there any precautions should
I take?
Take the same precautions you'd use if you were
going on a hike. Tell someone where you're going and when
you expect to return. Bring maps, water, sunscreen, and
maybe a cell phone if you have one. Watch out for poison
oak, ticks, snakes, wildlife (both 2- and 4-legged). Above
all else, bring your common sense with you!
Can I use FRS / PMR to find out if other
Geocachers are in the area?
Yes. The community has decided on channel 2 as
the primary for both FRS and PMR, and 12 as the alternate
FRS (Family Radio Service) channel and 8 for the alternate
PMR (Europe). FRS and PMR radios are longer distance walkie
talkies, like the Motorola Talkabout. You can often pick up
a cheap pair of FRS radios for under $20 at discount stores
(Wal Mart, Target, KMart) and sporting goods stores.
What variations on the basic game
exist?
A number of variations have been developed so
far:
- Offset Caches - Here, the published coordinates are
that of an existing historical monument, plaque, or even
a benchmark that you would like to have cache hunters
visit. From this site a cache hunter must find offset
numbers stamped / written in or on some part of the
marker site, or continue based on posted instructions in
order to find the final cache.
- Multi-caches - The published coordinates are for a
small cache, which contains
coordinates (sometimes only partial coordinates) to the
next cache, and so on until
the final cache is found.
Sometimes multiple caches
have separate hints to the final cache's location.
- Virtual caches - Here the "cache" is actually an existing landmark, such as a tombstone or statue (so there's no container of goodies, or even a physical log). You have to answer a question from / about the landmark and pass this along to the cache owner as proof that you were there. Normally, virtual cache listings are only approved for sites in areas where normal, physical caches are not allowed (cemeteries, public buildings, etc.).