RogerBW's Blog

I finally tried geocaching. So far it's not a bad excuse for a walk.

I signed up at geocaching.com; they really want you to use their app, but I suspect the Android version relies on Google libraries that my LineageOS phone doesn't have, as it displays the sign-in screen and than crashes. Fortunately I already have OSMAnd (and some experience using it on walks), and the site lets you download standard GPX files which can be loaded into it. (I should write a thingy to strip together multiple GPX files into a single group, and move the descriptions into a field that OSMAnd will display. I hate XML namespaces; they may help with validation, but they make everything harder when you just want to get data out.)

There were two caches conveniently near home in roughly the same direction, so I set out to see what I could find.

These birds believe they are camouflaged.

Getting to the right spot within the accuracy of the GPS receiver was easy. But then I was faced with this. (Well, not exactly this, because that would be a Clue, but something quite like it.)

With a bit of thought ("if I were a moderately non-obvious item, where would I be?") I managed to locate it. This was an airtight food container (though it had clearly got water inside at some point), with logbook and various plastic toys.

On the way back; in this modern age, I could check for passing trains and determine that there wouldn't be anything for at least twenty minutes so it wasn't worth waiting for one.

The other site was a bit more of a challenge (a "nano" cache, in this case a plastic tube about 6cm long and less than 1cm wide with just the log sheet rolled up in it) by a relatively well-used road. It was while I was waiting for a good moment to retrieve it – one of the rules is that you don't do this stuff in sight of normal people who might not understand – that two bits of knowledge clicked together, and I realised that this is basically dead-drop protocol: don't make the location obvious, just casually walk past and scoop the thing up or put it down in an entirely normal and relaxed manner as if you are doing something entirely usual. Well, I can do that…

(Indeed, I am told that a somewhat parallel system is used by drug dealers in some places: you send them the money for a standard packet of whatever, and they tell you the location of one that they've already hidden somewhere.)

Of course, that's two out of the five live caches that are within an easy lunchtime walk from home, so I may start going further afield.

I gather it's traditional to leave small plastic toys in a large cache, and there's this convenient generator for random 3d-printable puzzle boxes…