This is an offset-multi cache on the site of the of the landfill of much of the rubble from the Christchurch earthquake events. The posted coordinates will take you to a five-fingered man-made structure with a bench in front of it that you can sit on. Looking at the five fingers, one of them has a single open hole in it above head height. Others have more than one open hole, and some don’t have any open holes at all. You want to the one with exactly one open hole in it.
If you were to look through that hole from the bench (which you can’t because there is something blocking the hole that I could not get out) then that is the direction you want to walk or bike to find the container, which is located 45m from the posted coordinates.
You are looking for a camouflaged 180ml Sistema container.
Please be careful of the plantings as you search for the cache. It might be best to enter GZ from the other side of the obvious foliage island by walking around.