Find this as part of the wherigo series.
You can find the cartridge at http://www.wherigo.com/cartridge/details.aspx?CGUID=a94b60e8-0107-4831-bf8b-929f332226df
There are five caches that you will have to find. If you do find them it will unlock ans send you after the number six. The final of the cache has some unactivated geocoins in it, and some other things.
If you or your caching group get there please only take one geocoin per group. So decide before you head up or flip a coin. I just would prefer that three people not go up together and take all of them.