The cache is placed at my favourite of several picturesque spots along the public lakefront walkway between Stoney Point and Waitangi Bay along the western shore of Lake Tarawera.
There are marked access points to the lakefront walkway dotted at intervals along Spencer Road. The closest access path is from the end of Waitangi Road. An alternative approach is to park at Stoney Point, which has toilets and a playground, and walk approximately 1.5kms along the lakefront to the cache (the walkway starts at the far end of the grassy area north of the playground).
You are looking for a small sistema with only a notebook inside. Reception is limited at GZ (and along most of the walkway), so save the cache listing before heading out.