Put simply, it's Treasure Hunting using Handheld GPS receivers.

Someone hides a box, records the coordinates, and lists them on www.geocaching.com 

To date, there are over 21,000 active Geocaches in the UK, there is probably at least one within a few miles of where you live. 

The rules are very simple.

1. Take something from the cache

2. Leave something in the cache

3. Write about it in the logbook

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