Probably the most popular walk in the Karangahake Gorge is the Windows Walk. It is a must-do if you like a combination of gold mining history, great views and river gorges.
The walk starts at the Karangahake Reserve, off State Highway 2, and follows a tramway that enters an old gold mine tunnel inside the cliff on the east side of the Waitawheta River. As you follow the tunnel, there are various points where” windows” were cut in the side of the cliff to give miners the benefit of the view, no doubt(!). You can also explore the odd mine shaft. But take a good torch, as your cell phone will only get you so far …
After the tunnel, you can continue on the east side of the river gorge for a while (it's very picturesque) or cross over to the other side to return to the reserve.
All up, only about an unhurried hour or so for the loop.