An EarthCache is similar to a Virtual Cache in the way that there is no traditional cache container or a log book, but because of their purpose they differ greatly.
The purpose of an EarthCache is to share information about a particular geological feature of our planet Earth, and the object is to learn something about it. When you visit an EarthCache, you learn something interesting about the geology of the area. Usually the information is freely given but you have to do a bit of investigative work to answer proposed questions in order to claim the cache.
EarthCaches are created by Geocachers who have knowledge of geoscience and like to share it with the world.
–Taken from Geocaching Online
In honor of Labor Day, I found my first Earthcache. I’ve forgotten a lot of my Geology 101; I think I’d like to take a refresher course this summer.