One of my favourite walks in NZ. About an hour return though old mining tunnels cut into the hillside. Bring a torch!
Further information:
The Karangahake Windows Walk is a fun and exciting 2.5 km loop experience located in Kaimai Mamaku Conservation Park and Karangahake Gorge within the Bay of Plenty region. With beautiful scenery and spectacular mining remnants including disused gold mining tunnels, it's sure to be a great experience for everyone. Visitors can begin by crossing both the suspension bridge over the Ohinemuri River, and then the Lower Waitawheta Gorge bridge. Afterwards they can explore the abandoned buildings and machinery of the Talisman battery and view the four openings (windows) of the old mining tunnel which look down on the dramatic river gorge far below before eventually returning to the car park. A torch is highly recommended for the Gold Mining tunnels.