An obvious recommendation was to stop at Karangahake Gorge and to do the Windows Walk, where you walk along gold mining remnants and through a dark mine tunnel (torches highly recommended).

Steffi & Gerry: Trip around the World
Travel Blog of our Honeymoon around the World
An obvious recommendation was to stop at Karangahake Gorge and to do the Windows Walk, where you walk along gold mining remnants and through a dark mine tunnel (torches highly recommended).