7 Mystery and Puzzle Ideas

As geocaching has grown, the challenge of the game has changed in many ways. Increased awareness has brought more regulations and restrictions for caches hidden in State Parks and other managed areas. These developments can lead to frustration in cache placement and lower the level of difficulty involved in the game. While everyone enjoys logging a smiley and the occasional roadside micro can be refreshing, too many caches with too little challenge can lead some to ask, “Where’s the challenge in this game?”

A wide variety of challenges can be applied to geocaching. There’s the obvious physical challenge of a long hike out in the middle of the woods to retrieve a cache. There’s also the stealth challenge of searching for an urban cache without being spotted by non-cachers. Another challenge exists in hiding the coordinates for the cache and requiring seekers to work a puzzle, crack a code or solve a mystery before finding the cache. Where the availability of challenging locations might be limited, a puzzle cache can generate a lot of attention and excitement even if the location is far from five-star.

You only need to look at the number on the watchlist of a good mystery cache to realize what kind of attention these caches generate. They are often the topic of discussion at events and in local email lists. I’ve known cachers to search the online logs for hours for any hint that previous finders might have dropped on particular mystery caches. I’ve also known the reality of good-natured threats to have my legs broken over some of my own mystery caches. It’s all in fun though?uh?right?

Unfortunately, a lot of us didn’t grow up working the kind of mind-numbing puzzles that are often applied to these caches. The thought of putting together a mystery cache eludes us and we have no idea where to begin. As I’ve looked over a lot of cache listing from various locations I’ve noticed that there are a few tried-and-true methods of hiding mystery caches that seem to translate well to just about any area. So, for those of you who need a little jumpstart when it comes to putting one of these caches together, here is a dossier of seven mystery and puzzle cache ideas that will get your creative juices flowing and might just get the locals talking.

Kids today! They spend hours and hours playing with their video games and rotting their brains out! When I was a kid we spent hours and hours playing with Rubik’s Cubes and rotting our brains out. Sure, the effect was the same, but we used fewer batteries.

Give cachers a blast from the past with a Rubik’s Cube based mystery cache. This can be done as a two-part mystery. At the first location hide (in a waterproof container) a Rubik’s Cube (you can still find these in toy stores, by the way).

With the cube in solved position (all sides correct), etch the final coordinate onto the individual sides. Don’t skimp on this step. Simply using a waterproof marker won’t work; sooner or later the numbers will rub off. A Dremel-type tool with an engraving bit will work fine.

Part of the fun with this one will be getting them to figure out which side of the cube to start from. The cache I found like this had the latitude coordinates running horizontally and the longitude running vertically (very apropos). You could go that way, or run both of them horizontally?longitude on the top row, latitude on the second row and include a hint on the third row. It’s really up to you. Just be sure to decide what you’re going to do before you put the engraving bit to the cube.

There are a couple cube caveats to be aware of. First of all, make sure you explain on the cache page that the puzzle needs to be reset (mixed back up) after they solve it. Second, be aware that there might be those who will attempt to solve the puzzle by taking the cube apart (that’s the only way I know how to solve them). Offer a stern warning on the cache page about this or you might find yourself in need of more Rubik’s Cubes.


Rubik’s Cube 25th Anniversary
Rubik’s Revenge (an interesting variation)

Remember Ralphie from “A Christmas Story” and his eagerly anticipated Little Orphan Annie Secret Decoder Pin? That much-valued premium was a code wheel, a tool that has been used in the spy industry for years. In its simplest form it consists of a wheel inside another wheel, both containing letters A-Z and numbers 1-0. By turning the wheels and realigning the numbers and letters you can come up with over 1000 possible code combinations. The inner wheel can provide the encoded letters and the outer the actual message.

Click here to for a printable PDF version of the code wheel.

Your use of the code wheel can be as simple or as complicated as you want. Proved a link for cachers to download the wheel (use the one provided by Geocacher University if you would like), and provide them with the proper code key. For example, the code key “A4″ would translate the phrase, “You will find the cache at N 39? 22.119 W 087? 21.576″ as “6V2 4PSS MPUK 1OL JHJOL H1 U0F? 99.88F 4GED? 98.BDC.” All it would take for the coordinates to be decoded is a printer and a few minutes of work with the wheel.

If that’s too easy then hide the proper code key somewhere on the page or don’t give it at all. A little logic should be all it takes for people to discover that in the coordinates “U” must be “N” and “4″ must be “W.” To complicate it further use the code wheel in conjunction with a multi-cache and change the code key for each step. That should keep people busy!

This style of cache is a great bonus for kids who are involved in scouting. Code work is considered to be an elective in Boy Scouts. It might be a good idea to consult your local scouting troop either before placing the cache or to invite them to come out and search for it.


Wheel Cypher Cache

Emmett’s Nightmare
Emmetts Nightmare used two poems/short stories available from Project Gutenberg. org. You had to count the words in this poem/story using the numbers given in the nightmare story on the cache page. The first letter of these words when combined spelled out the numbers of the coordinates. To add to the evilness I spelled out North and West and if the poem/story didn’t have the letter I needed (z) I placed ???

As technology continues to change and evolve, geocachers will no doubt keep in step with caches that take advantage of new developments. This has been very evident with the recent podcast revolution. With the simple addition of one more geeky gadget (an iPod or other brand .mp3 player) you can add a whole new dimension to geocaching?an audible one!

In order to make this cache work you’ll need a digital recorder and a site to upload the .mp3 file you’re going to create. Digital recorders can be found fairly cheaply these days, but keep in mind that skimping on quality could cause some problems with the recording.

Remember: GPS usage must be an integral part of finding the cache You’ll need to use your GPS to give seekers the starting coordinates. Once they’re at that spot the audio tour begins. Instruct them on the cache page to turn on their mp3 player and-through your recording?give them cues as to which direction to go and when to turn. For some extra fun and clarity, you might want to include some compass use too.

You’ll want to keep your instructions simple and understandable. Also keep in mind that seasonal changes may effect the instructions you give. Try to look for permanent landmarks that will be easy to spot in any conditions.

The level of detail you give could depend on where you place the cache. If you placed it in an historic or touristy spot, you might want to call attention to some of the local sites. You may want to use colorful descriptions that make them think (like “The Big W” from “It’s a Mad, Mad, Mad, Mad, World”). One audio cache I saw used musical clues with snippets from different songs. It also might be a good to give people an idea of what kind of pace you’re expecting them to walk through the audio tour.

Another type of podcache hide might take seekers on a tour of an area looking for clues to plug into the final coordinates. “Coming up on the right you will see a fence, count the number of vertical poles in the fence. This is letter “C” in your final coordinates.” After finding all the clues with their mp3 player, the cacher would then go for the final cache using their GPS.

If you’re looking for some great examples of podcaching, as well as some helpful instruction on podcasting, check out the Podcacher Podcasts. Be sure to especially check out Show 10: Audio Recording 101 for tips and tricks on putting together your own recordings.


Podcache in the Park
Horsetrail Huff – A PodCache

Guidelines for Placing a
Mystery/Puzzle Cache

As with all caches, mystery caches have to go through the review process. There are specific guidelines to follow as well as a few matters of etiquette that should give you some guidance as you put your cache together.

  • For clarity, you might want to include the words, “The cache is not at the posted coordinates” in the short description on the cache page. This is a great courtesy to those who might not otherwise realize that it is a mystery cache.
  • According to the guidelines, “Unless a good reason otherwise can be provided, the posted coordinates should be no more than 1-2 miles away from the true cache location. This allows the cache to show up on the proper vicinity searches and to keep the mileage of Travel Bugs that find their way into the cache reasonably correct.”
  • Keep in mind your cache needs to be solvable on the cache page itself. If you require cachers to email you for the final coordinates chances are your cache will not get published.
  • Use the “additional waypoints” feature to provide your actual final coordinates to the reviewer. Be sure to check the box to keep them hidden from everyone but you (the hider) and the administrators.
  • As always, Provide your reviewer with as much information as possible. This usually means that your review will go quicker with fewer questions. In some cases your local reviewer might ask for some explanation as to how the puzzle works. Be sure to cooperate with these requests in reviewer notes on the cache page.
Sometimes a mystery cache is all about finding the coordinates, other times it’s all about trying to get into the container. One technique I’ve seen a few times is to padlock an ammo can. Attach an eyebolt through the hole in the latch. After closing the lid a padlock can be placed through the eyebolt and the lower wire handle, effectively locking the cache.

On one occasion, a multi-cache required you to find a particularly difficult micro stage, which contained the key to the padlock. From there, you went on to the next stage to find the locked ammo box. While this was fun, there are certain maintenance issues to consider. Sooner or later someone will lose the key and then someone will lose the extra key. Get a set of bolt cutters ready.

Another option is to use a combination lock and provide the combination through one or more other steps in the multi. No more problems with losing the key!

There’s now a new spin on this tried-and-true technique. Wordlocks are a unique new type of combination lock that uses letters instead of numbers. They come in a variety of colors and can be set to 100,000 possible letter combinations including over 1000 four or five-letter words (instructions are included along with a list of sample words in case you aren’t much of a speller).

The lock itself is unique enough that it offers a variety of methods of execution:

  • Hide the secret word in the cache page itself.
  • Design a crossword or word search puzzle to guide cachers to the correct password.
  • Use a word found on a sign near the cache location.
  • Use the name of a local cacher and hide the cache in honor of him/her.
  • Write the codeword on the inside of the lid of another cache.

There are many other possibilities out there. Give it some thought and come up with something new and original.

One other thought about this idea: many cachers are helpful and willing to share information with others about how to solve mystery caches. If you make the puzzle exceptionally difficult you can expect your password to get?.well?passed around. But since you have the ability to change it over and over again, there’s no reason you can’t keep the puzzle fresh.

If you’ve never heard of Sudoku, you’re not living under a rock in a classy enough part of town. This horribly addictive number puzzle has captured the attention of old and young alike. I was working a puzzle on my Palm while waiting my turn to get a haircut a few weeks ago and an elderly lady next to me told me about the aggravating grid she had worked that morning. Upon seeing my Palm she commented that she might need to buy one of those just to play the game on.

Sudoku is a number puzzle that involves no math and a lot of logic (eh, it’s a fair trade off). It’s played on a 9×9 grid in which each number from 1-9 can appear only once in each line (horizontal and vertical) and only once in each 3×3 square. It will only take a few minutes to get the concept in your head but many many hours to get the game off your mind. The game is either simplified or complicated by the cells that are filled in for you when you start. The more numbers they give you the fewer leaps of logic you have to take to arrive at a completed puzzle. Got it?

Sudoku (actually “Su Doku.” Loosely translated it’s Japanese for “solitary numbers”) naturally lends itself to puzzle caches. By assigning letters to the horizontal grid (A-I) and numbers to the vertical (1-9) you can direct cachers to individual cells within the grid (as in the image to the right).

So how do you put one together? You have a couple options. One, you can find a pre-made Sudoku puzzle and direct people to the squares of your choice (keep in mind, if there’s a zero in your coordinates you’ll need to give that one to them). Or you can go to Sudoku-XLS and download a Microsoft Excel document that helps you create your own puzzles.

Of course, it’s up to you to decide how easy or difficult you want your puzzle to be. Many Sudoku sites rate their puzzles as either Easy, Medium, Hard, or Insane. It all depends on how many pre-filled squares you provide for the players.

A couple things to keep in mind about this style of hide:

  • With nearly 400 different Sudoku-based puzzles hidden at the time of this writing, it’s going to take some imagination to keep this style fresh.
  • There are many Sudoku solving programs available out there. Chances are some of your finders will use these rather than solving the puzzle themselves. If you’re ok with that, then no problem, but you might want to find some way to work around this problem.


Wheeling Sudoku
The Ultimate Sudoku Challenge
A very good example of how to keep this style of hide fresh!

They say that a picture is worth a thousand words, and a well-done picture puzzle cache can certainly generate a lot of words. Some of them aren’t the kind we use here though!A good picture puzzle not only challenges the finder to get to the coordinates but to get inside the hider’s head to find exactly what you want them to look for. I’ve seen some great puzzle caches built around either a single picture or multiple pictures on the cache page.

One common method for this style of puzzle is to provide a set of pictures that correspond to the numbers in the cache’s coordinates. One puzzle I’ve seen had a series of Presidential portraits. To find the cache you had to identify which President was which (difficult to do with some of our lesser-known Presidents) and then identify his place in the sequence of office (example: Washington = 1, Lincoln = 16, etc.). The number in his sequence corresponded to the coordinates needed to find the cache.

The great thing about a puzzle like this is it can be applied to a wide variety of topics to keep the challenge fresh. Instead of using Presidents, try state flags (corresponding with their entry into the Union). Another example I’ve seen used book covers from a numbered series. The possibilities are practically limitless with this kind of puzzle.

For a different kind of picture puzzle, try a “Magic-Eyes style” 3D picture creator like the ones found here. It will take some practice to come up with one that works well, but it will be worth it!


Presidents Day
UPC – Unique Puzzle Cache

Verify Verify Verify

Many cachers like to verify their coordinates before going after puzzle caches. Usually this means emailing the owner and asking for confirmation that you’ve solved the puzzle right. However, thanks to a couple of new websites, it’s now a lot easy to get the verification you need to find those mystery caches.


Both of these sites offer the option of exact coordinates or “fuzzy” coordinates for those puzzles that just get you to the general area of the cache. They also both offer security to keep people from making many guesses at the correct coordinates until they get them right.

And for those of you who are a little more security minded, both sites promise that unscrupulous cachers won’t simply be able to tap into their database and find your correct coordinates. Not that anyone would really do that anyway . . . right?

Remember back when home computers first really took off and suddenly there were hundreds of fonts available with which to express yourself? Remember those friends of yours who would send you their “family newsletter” and assign a different font for each article? Do you remember how annoying that was to read?Well, who better to annoy now than your fellow cachers? There are thousands of fonts out there for the taking. Many of them fall into the “Dingbats” category, using images rather than recognizable letters. These can be used to create some puzzling codes for your coordinates.

For example, the font used below is called Wingdings and is included with most Windows-based PC’s. The coordinates provided, when switched to Wingdings look like this:

With the incredible number of fonts available the ideas for this style of puzzle are practically endless. You can use:

  • Dingbats: A specific class of font that uses pictures instead of letters.
  • Braille: Braille fonts and even Morse code fonts are both available from a variety of sources.
  • Klingon: This is a real fun one for the geeks out there. There are lots of fonts available that build off of languages made up for various science fiction series and movies.

Keep in mind, not everyone has the same fonts installed on their computers. In order for this puzzle to work, you’ll need to do a screen capture of your text and paste it as an image file into your cache page.

FontFile – The most extensive collection of dingbats and fonts on the Internet.


First City Want Ads
Hubcap IV

Final Thoughts

Puzzle caches can often provide both seekers and hiders with a badge of honor. There are few things more satisfying than cracking a code and getting a reward . . . except maybe creating the code that drives everyone nuts!

Be aware though, while puzzle caches will draw a lot of attention, they might not draw a lot of visitors. Cachers from out of town will often overlook mysteries and puzzles because they just don’t have the time to put into solving them. Even some of your locals might choose to put off doing them until they have more time to work out the details.

Also, be aware that sometimes puzzles that make sense to the creator don’t always make sense to those trying to work them. Have some friends “test drive” your puzzle to help you work out any bugs.

One final caveat about puzzles: it’s very common for cachers to take an idea they’ve seen somewhere before and create a similar puzzle in their own area. Always remember to adapt rather than adopt. That is, don’t just copy the puzzle cache from someone else, use the principles you learn from it and create your own. Who knows, your’s might end up being even more puzzling than the original.