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This new site (www.geocaching.com) enabled the sport of geocaching to grow fast and spread quickly to what it is today (nearly 121,000 geocaches in 210 countries as of Sept 2004). The appeal of geocaching is easy to understand — it makes real our childhood dreams and fantasies of treasure hunting and combines that with hi-tech yet affordable gadgets, a massive online community, and the great outdoors.
Geocaching Made Simple
Before we look at geocaching-specific hacks and software that might be of benefit to you, this section explains a little bit about geocaching in case you aren’t sure what it is. If you are already familiar with geocaching, you might want to skip this section.
For more specific information on geocaching, visit one of the following websites:
www.geocaching.com
www.navicache.com
www.brillig.com
http://geocaching.gpsgames.org
What Is Geocaching?
In its simplest form, geocaching is a modern-day treasure hunt. There are no sailing ships or pirates, and instead of using an old map with an X to mark the spot, you use the Internet and your GPS. Instead of a treasure chest filled with gold and jewels, the treasure is a plastic lunch box or an ammo box (or maybe even something much smaller) filled with small trinkets and a log book. (Who knows? You might be lucky and find a treasure chest that’s bursting at the seams with riches. I’ve never come across one, but if some kind geocacher wants to hide one, I’ll sure have a go at finding it!) The object of the game is simple: find the cache.
There can be more to it than that — some geocachers like to be the first to find a new cache (finding a new, unlogged cache is called an FTF), while others might attempt to find a certain number in a day or a year, whereas others just enjoy it for the sense of adventure and the new places they discover. These are all variations on the same theme. What always matters is finding the cache!
So, what’s the process involved? The following section explains geocaching, compressed into a few simple steps!
Geocaching from Beginning to End
Here is what geocaching is all about, from beginning to end:
1.Someone has to prepare a cache and hide it somewhere. This person is called the cache owner or cache hider.
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2.Different listing sites have different rules, but there are a few commonsense rules that anyone placing a cache should follow. To avoid disappointment, make sure that your cache follows the rules of the listing site. Some of the most common rules include the following:
■No alcohol, tobacco, firearms, or drugs in the cache. If possible, try to populate the cache with “family-friendly” items.
■At the very least, your cache should contain a logbook and a pencil.
■No food or drink in the cache — animals will sniff it out and at best trash your cache; at worst, they may get stuck in it or become ill as a result.
■Get the landowner’s permission before placing the cache.
■Take care not to hide caches where many cachers coming to search for it might damage the environment. This also means no burying of caches.
■The person placing the cache assumes responsibility for maintaining it.
3.The person placing the cache should accurately (or as accurately as possible) use a GPS to get the coordinates of the cache he or she places. The more accurate this reading is, the easier it will be to find the cache.
4.The cache hider then registers the cache with a cache listing site (basic membership of the site is free). This involves filling in a form detailing the cache location. Some people also provide a short description of the cache or a clue as to where it is hidden. The clues are normally encrypted using a simple ROT 13 system whereby A = N, B = O, C = P . . .
X = K, Y = L, Z = M. Don’t worry, though, you won’t have to encrypt the clue manually, as the system does that.
You can also have the clue decrypted automatically too, either on the website or by one of the many geocaching software aids available.
5.The cache will then be approved by the listing site (or declined with an explanation). It is at this stage that the cache details are made available for others to see.
6.Other geocachers now visit the listing site, choose the geocaches they are interested in visiting, and download the details of the cache (or print out the information).
7.The geocacher then loads the coordinates onto his or her GPS and sets off to try to find the cache. This might seem easy but trust me, geocachers can be clever when it comes to hiding.
8.If the geocacher is successful in finding the cache, he or she fills in the logbook, swaps a trinket or two, and replaces the cache.
9.When the finder comes home, he or she accesses the listing site and logs the find.
That’s it! That’s geocaching! There are many different kinds of geocaches and many variations on the theme, but the overall idea is the same — to find a specific object hidden somewhere on the face of the planet and log it. Only the pinpoint accuracy of the GPS enables ordinary people to achieve such a level of precision. This level of accuracy goes well beyond what anyone could expect from a map and compass.
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One variation is the use of travel bugs. These are trinkets that move (with the help of other geocachers, of course) from geocache to geocache. Their movements are logged online and their progress monitored.
Just think about it for a moment and I think you will be impressed. I can take an average lunchbox and place it anywhere on the Earth (with a view of the sky) and give you those coordinates, and you will be able to navigate to it to within a few yards thanks to a handheld receiver, access to a constellation of satellites orbiting the Earth, and billions of dollars of hardware.
Once the GPS has taken you to within a few yards of the cache, the rest is up to you. You might need to have a good scrabble around the place before you find it. However, at least you are now looking at scouring an area a few tens of square yards (see Figure 11-3) . . .
FIGURE 11-3: A smaller area to search in
. . . rather than hundreds of square yards (see Figure 11-4)!
So how do you find the cache in the last 20 yards? Many cache listings, but not all, will provide clues as to where the cache is hidden, such as “in the roots of the rotten tree.” Of course, you will often find that there are many such rotting trees in the search area. This is where your GPS skills really come into play!
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FIGURE 11-4: A far bigger search area!
The Final 20 Yards
You’d think that after getting to within 20m or so of your desired location with a GPS, the final few yards would be a walk in the park (pun intended!). After all, GPS manufacturers boast superb accuracy nowadays, so in theory you should be able to walk right up to the geocache and reach right under that log or in that bush and retrieve your prize. The truth is that, all things being equal, the final 20 yards or so can be the most difficult. Here’s why:
Your GPS isn’t 100 percent accurate! It doesn’t know where you are, it estimates where you are. There is a big difference. Remember that this is true of the GPS receiver or the person that set the cache, and if the conditions aren’t good, the error experienced by the person setting the cache compounds any error you are experiencing.
Playing the averages: As you travel, GPS in hand, the device is averaging your position all the way. The further you are from the cache, the less all these averaging errors matter because when you are, say, 1,000 yards from the cache (or 100 yards for that matter), the direction of travel arrow on your GPS is still going to point in the general direction you have to go.
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As you get closer to the cache there is a natural tendency to slow down. After all, the slower you go, the more accurate everything will be, yes? Well, in fact, no. Most GPS receivers rely on the GPS being in motion in order to determine the right direction to go (it uses the GPS signal as a compass, although some GPS receivers do have a built-in compass). Slowing down as you get nearer to the cache is not normally going to help you!
Cachers usually don’t hide caches in plain sight or on open ground. Look for things that stand out — a lone tree or a rocky outcrop. Usually, substantial tree cover is involved, which can interfere with the signal to your GPS receiver.
Remember too that the cache itself has been hidden — the geocacher who placed the cache doesn’t want to make your task too easy!
There are some other tricks that will help you too:
Don’t aim for the cache — aim beyond it.
Look for signs of disturbance.
Look for a break in the tree cover.
Use search patterns.
Stop and average.
Approach it from a different direction.
Look for the unnatural.
The following sections look at each of the preceding hints.
Aim Beyond the Cache!
This sounds like the logical thing to do. Walk and walk and walk until the distance reading reads 0 yards and then you must be there. You’ve been conditioned by the GPS receiver to count down the distance over however many hundreds or thousands of yards you’ve been walking, so it’s natural to think that this is what you can expect.
A far better trick is to aim beyond the cache — the GPS is unlikely to take you much closer than, say, 5–10 yards, so use this to your advantage. Note when your GPS unit indicates that you are 10 yards away from the cache and then keep going. The direction of travel arrow will probably begin to waver and spin erratically. Keep walking in the direction you were going and eventually the arrow will settle and point behind you. Keep going until you are about 10 yards away. Now stop. Look behind you to the location where you made a mental note of being
10 yards away from the cache and halve the distance between where you are and that point. That gives you a very good starting point for your search.
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Resist the temptation to slow down and stop when doing this 20 yard bit — this will only add to your errors! Rather than slow down, stop instead, letting your GPS receiver get a good fix before moving on.
Look for Signs of Disturbance
Chances are good that you’re not the first person who has looked for and visited the cache; and even if you are the first to find it, remember that the person who placed the cache has been there already! In other words, look closely for signs that others have been there before you. Many of the popular caches are dead easy to find because the previous cachers have left a wide trail in the undergrowth leading right up to the cache. In addition to this ground disturbance, many cachers, after finding the cache, sit themselves down near the hiding place in order to fill in the log book and do their swaps. Therefore, when hunting for a cache, think about where would you sit — it might just lead you to it!
Things to look for include the following:
Footprints
Flattened grass
Broken twigs
Garbage (sadly, trash is often found near caches — why not take a bag with you and clean it up? Cache in-trash out!)
Objects out of place
Other disturbances, such as overturned logs or rocks
These signs can quickly give away the position of a cache from many yards away. In fact, with a little experience, you won’t even need to look at the GPS when you are within 50 yards of the cache!
Look for Breaks in the Tree Cover
If the cache you are seeking is under tree cover, searching is going to be tougher. Leaves absorb the signal from the GPS satellites, which means that accuracy will suffer. Your best option here is to look for a break in the tree cover and then sit there for a few minutes until your GPS gets a good signal lock before resuming the hunt.
After you regain signal lock, start moving again, making a mental note of the direction in which your receiver is telling you to go and going that way. If you lose signal lock again, try to find a different break in the tree canopy and wait there for a few minutes again to get a good lock. Once you begin to move again, you should get a direction to the cache. If you are lucky, the direction that you are being told to go in will intersect with your previous direction — this will give you a good clue as to where the cache is.
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Search Patterns
You might find it very hard to get a good fix so you will need to adopt some search patterns. There are two that can help:
Spiral pattern search: Get to a position where you are quite close to the location given for the geocache (say, within 25 yards or so) and work your way around the area in a spiral pattern, checking possible hiding areas. This method gives you a good way to be methodical (see Figure 11-5).
Crisscross or grid search: This is for areas where you can’t get a good signal close up. Get to the general area of the cache (say, within 50 yards) and start walking up and down past the area where you think the cache might be hidden. If this doesn’t reveal the cache, try again, but this time work across the area instead of up and down. Again, work methodically and take your time (see Figure 11-6).
FIGURE 11-5: Spiral search pattern
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FIGURE 11-6: Crisscross or grid search pattern
Stop and Average
Some caches are just plain elusive; they may be well hidden under a log or rock, or in a massive field of logs and rocks. This can make things mega tricky. At this point, it might be a good idea to just take a break and let your GPS receiver get a good lock (a few minutes), giving you a good high-precision estimate of the distance to the cache. Then move a bit and let the GPS unit get another lock. Keep doing this until you have narrowed down the position of the cache.
This is a slow process but it does get results.
Approach It from a Different Direction
This is a simple but effective trick. Just overshoot the cache location and approach it from the opposite direction. Many caches are only well hidden from the direction in which the cacher thinks you will approach!