Kitekite Falls (also Kitakita) in Piha, Waitakere Ranges, is a superb walk through native forest, with large numbers of nikau and kauri rickers (baby trees). There is a short loop near the beginning then another as you approach the falls. Make sure you do both loops. The best full-height view is from the southern side of the loop to the base of the falls.
Once you hit the base of the waterfall, take the quite steep walk to the top. There are a couple of pools you can bath in, including one right on the edge. Truly spectacular all round.
Amazing to imagine, but in the 1800s, when colonists were busy cutting down all the trees, there was actually a dam at the top of the 40 metre falls for flushing kauri logs. They only tried it once!
Access to the walk is from the end of Glenesk Rd.