If you only do one hike on your Hana day, it is this one. The Pipiwai Trail climbs a gentle two miles through country that keeps changing the channel — a banyan the size of a building, overlooks into a waterfall-cut gorge, then a bamboo forest so dense it turns the light green — and ends at the base of 400-foot Waimoku Falls.
The trail, act by act
The path leaves the Kipahulu Visitor Center lot and climbs steadily on roots and worn lava. Half a mile in, the Makahiku Falls overlook gives you a 185-foot preview down into the gorge. Just past it, the famous banyan tree spreads over the trail like a small forest pretending to be one tree.
Then comes the part everyone remembers: the bamboo. Boardwalks carry you through acres of it, stalks thick as your arm and sixty feet tall, and when the trade winds push through, the whole grove knocks and groans like a ship under sail. It is one of the strangest, loveliest sounds in Hawai’i.
The bamboo opens abruptly to the amphitheater at the end: Waimoku Falls, four hundred feet of white water down a sheer, moss-black lava wall. Stay back from the base — rocks come down that wall regularly, which is why the park asks you not to stand under or swim beneath it.