Victoria Battery is the remnants of what was one of the largest gold processing plants in NZ. As this is a relatively young country, we don’t have many ruins, but I guess these qualify! The site covers several acres, includes a tramway, which still runs for tourists, many rusty bits of equipment, and the concrete sections of buildings that were too hard to remove. The old tank facility is particularly curious.
The runs are in the Karangahake Gorge, off State Highway 2. Park at Waikino and take the walkway under the road and over the bridge to the south side of the Ohinemuri River. If you are on a bike, the Hauraki Rail Trail runs directly through the ruins.