Running along the coast of the windward side of O'ahu lies a chain of mountains known as the Ko'olau. Jagged peaks and jungle-covered slopes make it an awe-inspiring area to visit. Translated from Hawaiian, Pu'u Manamana means "peak of great power." This is one of the most dangerous and infamous hikes on O'ahu, and it rewards you with views of the windward side that are unrivaled. Sheer cliffs hug each side of the razor-thin ridge trail, and steep ascents mean only sure footed hikers should attempt this adventure. The hike is not necessarily long, but it is definitely a challenge physically. Spectacular views of Kahana Bay and Valley, the Hui'lua Fishpond, and of the small town of Ka'a'awa will take your breath away.
Just like many hikes in Hawaii there is no official trailhead. Instead the beginning is marked with a fluorescent trail marker wrapped around a telephone pole that lets you know it's time to bushwack up the fern-covered hill. You will find this marker on the right-hand side of Highway 83 (Kameha'meha Highway) as you walk toward Ka'a'awa just past the Hui'lua Fishpond, which would be on your left. It is very steep right out of the gate, and you might need to use the roots and branches of the trees to help pull yourself up the hill due to the loose undergrowth that makes it tough to get footing. There are some ropes tied to the trees for assistance as well.
You'll emerge from the thick foliage after a few hundred yards, and you can look back to see the first overhead view of Kahana Bay. A picturesque scene unfolds with turquoise oceans leading to a white sand beach with a wall of jungle-covered mountains sitting overhead. On many days you can see surfers at Crouching Lion's break far below, named after the rock outcropping that resembles the animal.
As you head further along the trail, things begin to really intensify. The trail becomes narrower and narrower until it is just a few feet wide and flanked on either side by cliffs that drop for several hundred feet. The trail meanders to the south, where the true ridgeline hiking begins. Here the winds come from the ocean and are shot upward along the nearly vertical walls of the Ko'olau Mountains. The mountains trap the moisture that has been traveling undisturbed across thousands of miles of open ocean; the moisture is quickly condensed into clouds, making it almost impossible to see a day without at least some rain.
Needless to say this is not a trail for very windy or stormy days. Do not hike here after long stretches of rain, either, because the ground can give out when saturated. Even several days after a big storm there are reports of the ground giving way with deaths involved. Do not stand on edges made of dirt when resting or taking photos, and stick to the bedrock as much as possible. Eastern O'ahu is one of the wettest places in America, so make sure to take the weather seriously. All this aside, the hike is done by locals with some regularity. Just stay focused, smart, and prepared, and this can be one of the coolest day hikes you will ever do.