Jump to content

Building a Lab Cache in Hannover


Recommended Posts

We want to give some feedback on our experience so far. We hope this helps Groundspeak and also other lab cache builders! Would love to see some comments from the community. Thanks!


Building a few lab caches was a bit of a learning curve. The possibilities are endless. We created a total of six caches. Four of them are in connection with some local events during different dates. Here the link: http://bit.ly/Whto6Z


All of the caches are virtual caches. There is no physical logbook. Only a short code has to be found in order to log the cache. Before I go into detail about some of our caches, I would like to describe a few issues we want to give feedback on.


GPX File: MapSource was unable to open the provided gpx file. We also heard from other cachers about the same problem on other devices/software. Here the error one cacher sent us:


Öffnung Die_Abenteuer_des_Geoheimnisträger_.gpx

File: <unknown>. Line: 3 Col: 39 Error: Badly formed UTF-8 character in stream

File did not open.


Geofencing: once the first few cachers located the lab code at the event, the number of “finds” went up quickly. It seems the codes were freely shared online. One of the lab caches is not even available right now, because of the dates for that event. However, one geocacher tried 4 digit codes until one worked! He then shared that code. We had hundreds of “finds” for that particular lab cache before the event had started. We then changed the code to prevent further abuse.


We think it is important to incorporate geofencing when it comes to lab caches. A virtual cache should only be loggable when the cacher is within a certain radius of ground zero. The drawback: this excludes anybody who does not have a Smartphone. Is it possible to find another solution?


Details about the caches:


Two of the lab caches (Messe-Rallye) were part of a local event that took place over two days in October. Check out this

we made. You can turn on English subtitles. We hope you like it! Geocachers were given the code to a safe with free admittance coupons at the entrance. The goal was to find a number of QR codes we had placed throughout the event. Some were a little trickier to find and others were an easy scan. A Smartphone was of course needed to complete this task. Each QR code opened a page on a website we programmed. It kept track of the codes scanned and if enough QR were found, it revealed the 4 digit code needed to open the two treasure chests on site. Each chest contained a lab cache code.


The feedback we received from Geocachers was positive. Most would not have gone to that event, had it not been for the lab cache. They enjoyed the fact, that they were granted free entrance.


Two other lab caches have not yet started although they are part of the same series. I will write more about those caches in about a month or so.


The last two lab caches are not associated with a specific event. We wanted to mix it up a bit and also take this opportunity to show a wide range of lab caches. For example the lab cache “Mein Freund der Jasper” has a historical component. Jasper was a Robin Hood of Hannover so to speak. The house where he was born still exists and signs on the outside give information about him. This is ground zero for this cache. The finder needs to then call a specific phone number and enter the code. This starts a recording of Jasper where he will reveal the correct code for the lab cache. Feedback on this one has been great. Geocachers like how different it is from the normal caches.


Last but not least I want to mention, that because the lab caches are not listed on gc.com, we had to somehow let the community know that they exist. We posted in local geocaching forums and in different facebook groups. Our posts created quite a buzz for the first few days. We received lots of questions. Most of the feedback was positive.


Thanks for reading….. I will report more in a few weeks.

Link to comment


The last two lab caches went live at the end of October and most of the month of November.


One lab cache was called „Urlaub vor der Haustür“. Twelve vendors including ourselves were showing off our services to the public in a German department store in Hannover for three days. As part of this event we place little credit cards with holes in them at each vendor. Geocachers needed a piece of paper, find each card and trace the holes. After all stations, the four digit code became clear and our treasure chest could be opened. Not only could the Geocacher log the lab cache but everybody also had a chance to win great prices, like free entrance into the Hannover Zoo.



The last lab cache could be logged for several weeks. During the month of November, the city of Hannover had events on the subject of Science all over town. Different events took place every day. The cacher had to find a bicycle in Hannover by going to this website, which showed the location of the bicycle on a map. The bicycle then gave further instructions. It had to be moved to the location of a specific event that took place on that day. Once the bicycle was within 80m of that location, the digital display on the bike revealed the lab cache code. At least two events took place every day, so the bicycle could be moved as often as needed. We received lots of fun pictures from geocachers. Some even transported the bicycle via tram. Can you tell which of the three is the muggle?



Overall we think the lab cache series was a success. We hope some people felt inspired by our efforts. Thanks for reading!

Link to comment
We think it is important to incorporate geofencing when it comes to lab caches. A virtual cache should only be loggable when the cacher is within a certain radius of ground zero. The drawback: this excludes anybody who does not have a Smartphone. Is it possible to find another solution?


The drawback, it would include all cachers who doesn't have a charged smartphone with a mobile internet for the country where the lab caches are.


The benefit: it would make cheating slightly harder. But probably much easier than finding the sharing group.


What could help is requiring any kind of proof the cacher was there. But then we go effectively back to the virtuals.


Just a question: how did you manage to register the lab caches not connected to the Mega? You need a special permission from Groundspeak I suppose, but how do you get one? I've failed to find any information on this topic.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...