But don't do as we did, and imagine the rain will hold off for the 30km we rode to place the cache. If you don't have your bike, you can park close enough for a pleasant walk.
The cache is a black plastic clip-lock container attached magnetically. It's only about 11cm x 8cm, so don't bring anything terribly big.
Unless you can dislocate your shoulder whilst reaching for it, you will need to climb the fence. Sometimes this area gets quite wet, though it is dry for most of the year (previous iterations of this cache have floated away).