This is a wherigo cache. It's a really easy one - it will just take you to the starting location on the Poutu Canal, and then you'll head off to where the geocache is located.
Hopefully you will work out the theme of the geocache when you find it, but if not that's ok, it's still a bit of fun anyway! Hopefully.
To play the wherigo, you will need a wherigo player. Some Garmin GPS devices have the wherigo player built in, or you can use an app on an iPhone or Android phone.
You can download the cartridge here.
BYOP.