To get to the Waikane Trail, we went up the road past the Ka Mauna O Oliveta Church off Kam highway, and then on the right hand road into Watershed 6. At the end of the road is the old Waiahole Camp site and the now controversial Waiahole Ditch that starts way up in Kahana Valley and heads down the Koolaus to Waiahole valley where it tunnels through the Koolau range on its way to down to Mililani. The Waikane Trail begins left from the road and adjacent to the water diversion tunnel. It begins as a wonderful stone-paved trail winding up through the forest about 3/4 of a mile to the Kahana Saddle where the paved trail offers the hiker the choice of contining on down into the back of Kahana Valley.
I think the paved trail was built to facilitate the construction of the Waiahole Ditch. The Kahana Saddle lies between 2681' Pu'u Ka'aumakua in the Koolau range and 1683' Pu'u Koiele that rises above Pali Ku. This is way in the back of Kahana Valley. Wing describes an approach to Pu'u Ohulehule that, basicly, goes up Kawa Stream in Kahana Valley which is much more windward of the Kahana Saddle. Ohulehule can be approached from the Kahana Saddle as well, however, by following the ridgeline to the right. This approach is a very scenic, often times knife-like, and at times dangerously slippery route that leads over Pu'u Koiele and on to where it would meet the trail Wing describes. From 2265' Pu'u Ohulehule, which used to be quite scenic but now sounds overgrown, a loop return to Waikane used to exist that basicly drops down the ridge towards Waikane Stream and then follows the valley down about a mile to the road.
Also, from the Kahana Saddle, we used to go left on an obscure trail (actually, the continuation of the original Waikane Trail) contouring up the the back of Kahana Valley that arrives in about 1.5 miles at the summit of the Koolaus near 2681' Pu'u Ka'aumakua. The only real obstacle on this approach is a very narrow and crumbly barren rock cliff section that is best traversed when dry and face-to-the-wall for fear of plunging the 1000 or so feet straight down to the foot of the Koolaus inside Kahana Valley!
Once on the summit, one has the option of heading north along the sometimes washed out Koolau Summit Trail that runs 15 miles to Pupukea (if you don't bail out down one of the access trails along the way), south to the 2786' point that marks the intersection and end of both the Summit Trail and the Kipapa trail (Stuart Ball calls the 6 mile Kipapa the "longest, wildest hike on Oahu."), or four miles down to Wahiawa on the Schofield Waikane Trail that heads Ewa just a short distance north from where the Waikane Trail hits the summit. The hiker who overcomes all of the varied access problems will be rewarded with the experience of being in one of the most remote areas on Oahu. I can't describe it in words, but it is something uniquely Hawaiian and, especially for 21st century mankind, a humbling and purifying pilgrimage.