Directions to the trail head: Take Highway 50 to Waimea, continue through town, and go right on 550; look for the West Kauai Visitor Center on the far side of the junction where you will turn. Or if you want to see Kekaha, the last town before the end of the road, continue on and turn right on 552. Both roads join up a few miles. Follow signs toward Waimea Canyon and Kokeʻe State Park.
The road gently winds upward - there is one sharp turn - climbing the western edge of Waimea Canyon. You can stop at one of the turnouts for a quick view or continue to one of the main lookouts with parking and the most impressive vistas. The photo at right is from the first major lookout.
Park at the Puu Hinahina lookout which is clearly signed turning right off the main road. The trail head is at the back of the parking lot (see photo at left). Just to be clear, following the path off the parking area donʻt take the gated path on the left, you want the trail next to that heading into the woods.
Follow the trail through the woods a short ways before it begins to descend into a small side valley that connects into Waimea Canyon, but you will not have to descend that far. Nonetheless, the trail does drop a few hundred feet through a few switchbacks with very rough stairs formed by short logs placed perpendicular to the trail. At the bottom vegetation is much richer and you pass by an irrigation ditch that was built to collect water for the sugar cane fields (now gone) in the lowlands. Photo at right is what the area looks like viewed from the far side and above.
Climb up the other side of the valley and the trail opens out onto a clearing where you have a number of options. 4WD vehicles can get down here from Halemanu Road but I donʻt recommend driving a rental car here. The loop I took returns here. Heading down canyon - to your right - you quickly come to a fork. For a side trip you can take the signed trail on the right that leads a short distance up and around to a lookout over the valley you just crossed. (I didnʻt take this today. It dead-ends, retrace back to the fork to continue on further.) Canyon Trail officially starts here (to the left of the fork), proceeding first through more light forest and then out into drier terrain. There you will see a sign for Black Pipe which is a relatively short trail looping back to that clearing you just were at; this is a good option if you have gotten this far and feel like not making a full day of it.
Continuing now in more open, dry terrain you start to get great views of the canyon. Here the trail proceeds down canyon right in the middle between two tributaries of the Waimea River that come together ahead of you.
Slowly descending and further ahead you get a view all the way down to the ocean (it was a little hazy). In the foreground are what I am told are natural arch formations just left of center.
Be careful here as the trail fades and the hill just goes further and gets a little steeper and can be slippery with crumbled rock on the hard packed ground. Itʻs a long ways down in many places here.
From this open downhill sloping area the trail continues off to the left going into trees and descends a little more to the top of Waipoʻo Falls, actually just above the top of the big drop (when there is enough water) easily seen from the lookouts across the canyon. You canʻt see the falls from up here, or at least I wasn't up for going close enough to the edge, and I do not recommend trying (itʻs hundreds of feet straight down).
There are several branches off the trail leading to the stream, but to continue on Canyon Trail you want to go down to the lower part of the stream where itʻs usually easy to walk across on the rocks. As always, be careful around flowing water, rocks are slippery, flash floods happen, etc. and you are a long way from any road here.
If you take the first branch off the trail a little further up stream thereʻs a pretty little waterfall into a pool that makes a nice rest stop. However, even if you can get across, the trail does not continue from here; to go on go back to the main trail and cross lower down as mentioned above.
If you want to make a a shorter few miles hike, Waipoʻo Falls is a good point to turn around. If you crossed as per above the trail leads up and to the right. (Before learning where to cross I have gotten lost from this point, following a sketchy that petered out on my and required considerable back tracking.)
The next trail section leads through a couple of woodsy side valleys, climbing slowly up and finally curving left and out into more exposed dry terrain taking you up the ridge along which those arches mentioned earlier are. Donʻt try to head down to the arches, instead, take the trail onward leading away from them along the edge of the Poʻomau valley.
The trail follows the edge of the canyon and then ducks into the woods, down and up more side valleys, finally opening onto a grassy clearing accessible by another 4WD road.
Follow the road left (signage photo at right) back away from Poʻomau valley. Before long you will see (signed) Kumuwela Trail leading off to the left.
Kumuwela Trail is fairly narrow and at times overgrown but I had no trouble following it through the light woods, up and down a bit. This is classic Kokeʻe forest, set well back from the canyons. You will probably hear if not catch glimpse of many birds back here, especially if you stop and are quiet for a while after you get some distance from the roads (not that these roads see much traffic at all).
There is quite a lot of variety along this trail and at times the path is fairly overgrown.
At this point you are over halfway through the loop, at perhaps the extreme most distant point from the start.
This time of year quite a few flowers were in blossom. Having hike this previous in winter time though I can attest that there are plenty of flowers even then as well.
There was an unusual obstacle in the path - a large downed tree. I expect they will get in and cut this open but until then it isnʻt too hard to hop over the top, though that log is more than waist high at the lowest point.
The trail pops out onto another 4WD road.
Following the road you will come to a junction and see this sign: go right toward Kokeʻe-Halemanu Trail.
This is a tricky area: look for the two signs shown below.
Watch for the trail sign (photo above) just before the road bends left ahead of a private residence. If you miss it and go too far you will walk right up to the gate to Camp Slogget. Take the trail branching off to the right. Kokeʻe-Halemanu leads through more woods, similar to Kumuwela Trail.
Finally, Kokeʻe-Halemanu Trail descends and skirts the edge of a private home property coming out onto a 4WD road - go left. After a while the road passes a branch to Black Pipe already mentioned, and take the second left a branch: this is the 4WD road first mentioned that you saw early in the hike.
From there you are almost back: go right into woods leading down, by the ditch, and climb the trail back up to the parking area.
If you want to round out the day, you near to a wonder view point that overlooks Kalalau Valley, one of the most beautiful areas on the planet. Drive several more miles up the road into Kokeʻe, past the meadow, and stay on the road all the way to the end (thereʻs another Kalalau lookout along the way but I recommend the end of the road as best). Just a couple hundred feet a little up hill is all it takes to get some great views. I prefer the area just past the concrete viewing area, the terrain is easy here. Warning: the valley easily fogs up so best luck is going to be when it is sunny (I have gotten here and seen only white mist covering the entire area.) But the weather can change quickly here so if the view is blocked sometimes it will clear up surprisingly quickly.