Recently I did a lot of "geocaching". Geocaching is a GPS-based treasure hunt. All over the planet people hide small items (usually a small container with a logbook and sometimes small gifts), publish the exact GPS coordinates on platforms like or so that other people can load the coordinates in their GPS device or smartphone (there are many good apps for geocaching now!) and find the caches at extraordinary and magnificent spots. Here I would like to share my fascination with you, explain more detailed how it works and maybe motivate you to join this global community. Click here to find a PPT file that explains how geocaching works. If you are interested in learning more about GIS/GPS, mapping and geography in general, check this excellent source on Snugg (thanks to Tonya's girl scouts for the hint!).

Some years ago my best friend introduced geocaching to me. He had a GPS device and told me that he and his girlfriend took geocaching as a more exciting alternative for simply taking a walk: In our city Münster there were about 100 caches hidden, so all he needed to do is select one that is located in an appropriate distance, load the coordinates into the GPS device and it shows the linear distance and the direction to go. It is "exciting" because you never know where you will end up. Maybe 200 meters from the destination you find that you reached a dead end and have to find another way. Even a single wall can cause another kilometer to walk... Even though I was very interested in it I never made up my mind to buy a (rather expensive) GPS device. But when I got my first smartphone in Korea I found that there are very nice apps for geocaching. I chose the (android) app "c:geo" which works perfectly fine! All I needed to do was creating an account on so that I could connect to this large pool of caches around the world. If you are interested, you can watch my profile here:

 Profile for Magagpa

In 2014 I visited Singapore for just three days. I decided to make this trip a "geocaching trip": Instead of just pounding the sights, I wanted to see unknown places chosen by local geocachers by placing a cache there. It was a great decision! Telling you about this trip as an examplary geocaching experience is the best argument for doing geocaching!

On the first day early morning I took a subway to the southern coastline near the entrance to the island Sentosa. But before heading there I had two geocaches on my list (there are more than 1000 caches in Singapore, I had to choose a few). The first one was named "Sleeping Beauty". After running down a main road through a residential area and climbing some stairs up a hill, I quickly found the place: The tomb of an ancient Javanese princess called Radin Mas Ayu. The legend of her death (accidentally stabbed while attempting to save her husband, the prince, from being murdered) is told in the cache's description. Thanks to a hint in the description I could find the cache easily. "Root of tree" it said, and a huge tree's massive roots were very obvious:

After brief search I found the container in a hole of a root, and added my name to the log book. Later I also wrote an entry for the electronic (online) log. Actually, that is the whole reward: finding the cache, noting that I was there, and enjoying the surrounding area of the cache. Some caches contain little gifts, and the basic rule is: Only take something out when you can put in something else in return. The "treasure" geocachers hunt for is nothing material. It is the excitement of searching, the joy of finding, the moment of success, and then letting it go again and heading for the next destination. Sometimes I think, geocaching is just the excuse for adult people to do what they loved when they were Kids. It reminds me of my time as a boyscout, doing "Schnitzeljagd" (scavenger hunts) in our village or in the forest.

The second cache on my list was not far from the first and named "Passport not required". The compass guided me through the residential area with many apartment houses. But when I reached the spot of the geocache I found myself at a very special place: The tomb of an ancient Malaysian King! And his ancestors even still live there (in poverty in very simple houses) to take care of the tomb. The Singaporean government gave this area called Bukit Kasita (probably about 100 m˛) officially to Malaysia (but no Visa needed to access it, therefore the cache name...). According to some Islamic historians, the graveyard was opened in 1530. The tombs' headstones are covered in yellow cloth, a mark of royalty. This place is actually not marked in any tourist information that I saw. This is what I like most about geocaching: It brings me to special places that local people (those who hide caches there) know stories about. It even doesn't really matter that I couldn't find the cache here. The hint that I had to look at the roots of a tree didn't help since there were many trees with widely ramified roots. I felt observed by the local people who wondered what this strange guy is searching there. A general word about the "success rate" of finding caches: A good GPS device has a precision of about 10 meters. Sometimes it is very obvious what the actual hiding place could be within this range, but sometimes it requires long search. Many caches are very well camouflaged! I found hollow pebbles as containers (prepared by a geology student at Yonsei University Seoul), or a big fake nut (of a screw) on a metal scaffold in Taichung which took me more than one hour to discover! Sometimes (in my case in about 20% of the cases) I had to admit that I couldn't find the cache (like here). In some of these cases the cache might be actually gone, but I assume they are just hidden too well (which is necessary because people who are not intentionally looking for it must not find it accidentally). It also often happens that outer conditions keep me from searching thoroughly, mostly "muggles" (geocache language for "people") that just stand around and occupy the place. Usually geocachers don't want to involve people who do not intend to find the caches. Maybe a too curious fellow will take the cache and remove it...

From here I walked to the station of a cable car that took me to Sentosa Island, crossing parts of the harbour and some cruise ships, excellent view! On this tourist Island I walked through a small part of Jungle to try my luck at the North Western end of the island. The geocaching list located a special kind of cache here: an "earth cache"! Some people hide caches with an "educational mission", for example at places where geological or geographical phenomena can be experienced. See an overview of all common types of caches and how they are labelled at the end of this article or here. This earth cache named "It's sedimentary, my dear" is located at the cliff line of Sentosa (Siloso Point or Tanjong Rimau) and allows the visitor to see the geological history of Singapore, different phases of stone forming and sediments of different ages. The cache description is very long and gives a lot of information on this topic. Finally it gives four tasks which can be answered when finding this place and its waypoints (additional coordinates in that area included in this cache), for example "At waypoint 1 and 3, you will observe outcrops of stones of a dark colour. Describe these stones according to the dichotomous key and, hence, identify these stones.". However, this cache had an obstacle: It was a "tidal cache", that means it is only reachable at low tide since there is no road to there and it must be accessed by walking along the steep coast. I didn't check the tide times and had bad luck: the water was too high. Anyway, the attempt was worth it, because at least I found a very small but nice piece of beach with nobody around, so I relaxed a bit and found an impressively huge nut!

The next "Sentosa" cache was a traditional type again, hidden near the southern beach of the island at another historical place: a "Pillbox": a concrete bunker that was used in world war II as machine gun placement. Many of those fortified structures were built at strategic intervals along the coast of Singapore to ensure a continuous, overlapping field of fire, forming an important part of Singapore's WWII defence strategy against Japanese invasion:

The round trip around Sentosa Island continued along the beach to a very crowded tourist spot close to "iFly Singapore" at the Beach arrival Plaza. This traditional cache ("Ami's entrance"), a metallic container, was attached with magnets to the iron scaffold of a stairway, above head height below the stairs. The difficulty here was to spot and take the box without attracting too much attention from people passing by or sitting in or in front of the Cafés and Bars around this place. People must have wondered what this strange guy is looking for, strolling around that corner... After spotting the black box on the black-coloured scaffold (!) I positioned myself strategically well and faked some yawning and stretching, grabbing the box secretly, taking it to a nearby bench to write a log entry. Then I returned it in a similar way, pretending to wait for someone, looking around and at my watch... Mission complete.

Further east along the beautiful beach I discovered another type of cache: a "virtual cache"! This kind of cache does not have a box or item to find, it is just an outstanding, remarkable location that someone wants to share with others without having a chance to hide and maintain a container, for example a traveller who has no chance to come here regularly to check the condition of the cache (see table below). In this case the place indeed was special: From the beach a suspension bridge (about 100 meters) led to a small island. This island is claimed to be the most southern spot of mainland (continental) Asia that is accessible by land or bridge (Singapore actually is an island, but connected by bridges to continental Asia, Sentosa is again connected by a bridge to Singapore, and this little island has at least that rope bridge). The coordinates of the cache pointed to an information board showing a map that proves the legitimacy of this claim. Apart from that, the whole surrounding was simply stunning beautiful!



The next cache I planned to search ("Mad Macy's") had to be cancelled. I didn't read the description carefully enough: It was hidden in a small artificial island, 100 meters from the beach, without suspension bridge, so it requires swimming. I didn't bring my swim pants, so I had to walk back without completing the mission. I could have saved time and energy by having a quick look at the cache description, seeing the "requires swimming" sign. Let me explain some features of the cache information page. The user who hides the cache writes a more or less precise description of the cache and sometimes the surrounding area. Some texts contain useful hints or include photos. There is also space for an encrypted hint (but very easy to decrypt), but some cachers like to try to find the cache without the hint first. In addition to that, the hider can rate the difficulty and the terrain accessibility. It looks like this: One star means "very easy to find" or "accessible for handicapped", five stars mean "extremely difficult to find" or "extremely challenging terrain". Most cache pages I read had one or two stars. Next to this rating offers to give additional information in form of icons. All available signs are listed in this table:

Permissions Required equipment Facilities nearby Hazards Conditions
Dogs Access/parking fee Wheelchair accessible Poisonous plants Recommended for Kids Watch for livestock
Bicycles Climbing gear Parking available Dangerous animals Takes less than 1 hour Field puzzle
Motorcycles Boat Public Transport Ticks Scenic view Night cache
Quads Scuba gear Drinking water Abandoned mines Significant hike Park and grab
Off-road vehicles Flashlight Public restrooms Cliff / Falling rocks Difficult climbing Abandoned structure
Snowmobiles UV light Telephone Hunting Requires wading Short hike
Horses Snowshoes Picnic table Dangerous area Requires swimming Medium hike
Campfires Cross country skis Camping Thorns Available at all times Long hike
Truck/RV Special tool Stroller accessible


Recommended at night Seasonal access
    Wireless beacon Fuel Lost&Found tour Available during winter Tourist friendly
    Tree climbing Food Partnership cache Stealth required Private residence
            GeoTour Cache Needs maintenance Teamwork required

That was all on Sentosa Island. There are more caches, but I didn't have time and energy to check them all. The next day I went to the coast again, but further up East, with three caches on my list. The first one called "Big Splash!" was located near the first and meanwhile abandoned water theme park of Singapore (often the caches' titles are hints for where they are hidden). Due to a lack of GPS accuracy and many potential hiding spots I had to search for nearly one hour until I finally found it: under the rubber cap of a short pole holding a mirror (for traffic)! Some hiders are very creative in choosing their cache hides!

The next one was a multi-cache. This kind of cache involves more than one location. The given coordinates are just the initial spot. From here the cacher gets hints where to find the next stage, or clues where the final geocache might be hidden (for example numbers that need to be combined following a certain key to retrieve the final coordinates). In this case the description of "Missing Boy" revealed that 5 spots need to be found: a pedestrian crossing, a petrol kiosk, a police center, a bus stop and a green booth. At each spot the cacher would get letters from some mysterious hints. I imagined a huge traffic junction that has all these facilities, but was confused that my GPS directed me further away from main roads and into a park! I finally understood when I found myself in one of Singapore's "road safety community parks". It looked like a playground with miniature police station, gas station, three bus stops, Kiosks, even a car insurance building, and other structures. Kids were racing around with their bicycles, some practicing traffic rules with their parents, how to stop at traffic lights, etc. I was very amazed! I found the five locations, and at least at four of them I found little letters (G, B, I, D, R) after more or less long search with the given hints (for example: the hint for the "police station" was "Policeman:"...I spotted him hiding around the corner...", so I looked for a "corner", but a building has more than one corner, of course...). In one case (at the "bus stop") a father with his two children was very curious about what I am doing. I explained it to him and he told his Kids to help me searching. He never heard of geocaching before, but found it such a great idea that he promised me to get a GPS device and do this with his Kids in the future! I took this incident as a hint that it is not always necessary to hide this activity from "muggles" - sometimes there might be a new potential member of the global geocaching community! I knew one or two letters were missing, but the letters I had were very obviously pointing to a pedestrian BRIDGe (the E was missing), one of the biggest structures in the middle of the park. Indeed, I found the cache here, well hidden in the scaffold of the bridge.

The last cache for this area was directly at the beach, a kind of observation platform to either look at the uncountable ships at the horizon or to spot birds in the trees around the tower. The cache ("Look out!") was quite hard to find: it required a lot of patience! It was a small metallic tube, attached to the tower's railing with a magnet. There was no other way but touching the bottom of the whole balustrade (about 20 meters including the stairs). Luckily I found it after 5 meters. Blind touching or crawling around on the floor can sometimes be very unpleasant, especially when the cache is hidden at a spot with many bugs, spiders or other expected or unexpected animals, or with plenty of dirt. Here it was OK, but in other cases I rather gave up than risking bites or unlucky surprises or dirty hands and clothes...

On the third day I visited some essential tourist spots in the center, including the Muslim quarter (with a cache near a mosquee), Little India (with a cache near a Hindhu temple), Chinatown (no surprise: with a cache near a Buddhist temple), the Gardens of the Bay, Marina Bay sands Hotel and the Pier. Among many traditional caches I found I just want to introduce one more kind of cache: a mystery cache! The mystery cache requires solving a puzzle in order to get the correct coordinates. There are various kinds of mystery caches, some have links to online riddles, some need math or logical thinking, and some include objects or hints from a certain spot close to the final location to solve the riddle (and some mystery caches can actually be classified as multi-caches, too). I found one that asked me to take numbers from a memorial stone at a traffic junction in Chinatown following a certain pattern. These numbers combined were the exact coordinates, about 150 meters away from that spot. I found another memorial (that's why the cache is called "Lest we forget"!): iron statues of Chinese people suffering from the situation in WWII when Britain surrendered Singapore to the Japanese, a sad time in Singapore's history. The cache was a very tiny metal container, a so called "Nano cache".

The only cache type (among the common ones) that I did not describe here yet (because I didn't find one of those) is an "event cache". These caches point to locations where the cache creator plans a meeting and by this invites geocachers to come. That can be a meeting or Party of a local geocaching group or community, or a person's birthday party. Exact time of the meeting is given in the description. After that event the cache is archived and no longer displayed in the list or on the map. So far I never attended such a geocaching event meeting, but I thought about having a birthday BBQ in a park in my hometown that I could advertise by an event cache. I wonder how many geocachers would come...

Here is the overview of all cache types mentioned in this article:

Traditional cache

This is the original type of geocache and the most straightforward. These geocaches will be a container at the given coordinates. The size may vary, but at minimum, all of these geocaches will have a logbook. Larger containers may contain items for trade and trackables.

Multi cache

These geocaches involve two or more locations, with the final location being a physical container with a logbook inside. There are many variations, but typically once you’re at the first stage, you will receive a clue to find the second stage. The second stage will have a clue for the third, and so on.

Mystery cache

The "catch-all" of geocache types, this type may involve complicated puzzles that you will first need to solve to determine the correct coordinates. Mystery/Puzzle Caches often become the staging ground for new and unique geocaches that do not fit in another category.

Earth cache

An EarthCache is a special geological location people can visit to learn about a unique feature of the Earth. EarthCache pages include a set of educational notes along with coordinates. Visitors to EarthCaches can see how our planet has been shaped by geological processes, how we manage its resources and how scientists gather evidence. Typically, to log an EarthCache, you will have to provide answers to questions by observing the geological location.

Event cache

An Event Cache is a gathering of local geocachers or geocaching organizations. The Event Cache page specifies a time for the event and provides coordinates to its location. After the event has ended, it is archived.

Virtual cache

A Virtual Cache is about discovering a location rather than a container. The requirements for logging a Virtual Cache vary: you may be asked to answer a question about the location, take a picture, complete a task, etc... In any case, you must visit the coordinates before you can post your log. Although many locations are interesting, a Virtual Cache should be out of the ordinary enough to warrant logging a visit.