There are at least three way to approach the cache location. Along Campbell's Mill Road, from the Akatarawa side (the longest way), or from Whareroa Farm Park. You could also choose a variety of travel methods - mountainbike or on foot.
However, be prepared for exposed weather conditions up on the tops, and allow plenty of time to enjoy the views and the unfolding forest stretching back to the east. There is the option of making this a round trip and collecting other caches in the area if you plan accordingly
Cache is easy to find once you are at the site - theres really only one option!