Three cascading waterfalls and scenic valley vistas await along the Kaau Crater loop trail, a five-mile hike in the Honolulu Watershed Forest reserve behind Palolo Valley. Just 20 minutes from downtown Waikiki, this often-muddy trail follows the Waiomao Stream as it drains down and out of the crater. Follow the water upstream past portions in pipes to the top of the first waterfall, which empties far below into a small circular pool. Portions that follow require the use of a rope to pull yourself up cliff rocks alongside drop-offs, making this adventure also not for the faint of heart.
The second waterfall, not far from the first, rains down in silver ribbons into lush foliage with the trail at the base—you’ll have to scale the rocks alongside it, using another rope, to get up toward the crater summit. Along the way you’ll also have to ford rivers and even cling to tree roots where parts of the trail may be washed away. By the time you reach the third, and largest waterfall, you’ll have earned it. At the top, a small opening leads to a vibrant green and marshy meadow ringed by crater walls.
You can choose to circumnavigate the crater rim, which completes the loop—it’s recommended as this is where you’ll get those sweeping rewarding views of the Windward Side, Honolulu, and beyond, as well as the thrill of walking on trail just a few feet wide above drop-offs hundreds of feet tall. Along the crater rim there is a small offshoot trail that leads through forest, over a few small streams and right back to the parking lot. Otherwise, if you skip the crater rim, it’s back down the waterfalls, and back out the way you came.
The Kaau Crater Loop Trail trailhead starts at the end of Waiomao Road in Kaimuki. There is a small parking lot, enough for five cars, just past the Honolulu Diamond Sangha temple. This trail is recommended for moderate to experienced hikers only, and you should be prepared to abort the trip during times of heavy rains as the trail can become unsafe. Come prepared with proper hiking shoes, and plenty of water—plan for at least five, but probably closer to six hours to complete the loop and take in all of the sights along the way. Several tour groups take small groups along this trail and could be a good option for those wary of going alone or for the first time.