A half hour uphill walk to some historic mining remains.
There are a few access points, I recommend parking at the main Karangahake Reserve carpark along SH2 and taking Scotsmans Gully track. If the main carpark is full or you want the closest park, then you can park at the Mountain carpark (see P waypoints).
Trail directions:
At the top of Scotsmans Gully track, or from the top carpark, follow the gravel County Road track up for about 10-15 mins. Take the second turnoff to stay on County Road. After another 5-10 mins turn off the marked track at the given waypoint and follow the unmarked trail. In case the coords are out - the trailhead is about 8 paces uphill from the big pine tree. It's only about a minute's easy walk to GZ.