Ka’au Crater is one of three crater hikes on the island of Oahu (the other two are Diamond Head, a fairly easy hike, and Koko Head, a more moderate hike with a great cardio workout); it is the most intense hike out of the three, but also very rewarding. If you can push through the initial couple hours of walking through the woods, you will find yourself standing before three different waterfalls at three different locations near the end.
The trail is a bit tricky to get to and only has five dedicated parking spots available, so try to get there early if you want to avoid the extra walk. This trail can be very muddy, very slippery, requires the use of ropes (which are already on the trail), and has many high ledges you will have to walk or climb on and around. If you are afraid of heights, this trail may not be for you.
The majority of the trail follows a water pipe through the woods. As you can see to the right, the trail and water pipe are directly next to each other. Throughout the length of the trail, you will cross back and forth across a stream many times. Don’t worry, even if you’ve never done the trail before it’s very easy to find your way – just keep following the water pipe. You may also see bright orange or pink tape marking the path.
This initial section of trail is a few miles in length and can take a couple hours to complete. Bring plenty of water and some snacks. The first time I did this trail was with a friend and they did not warn me how long it was. I only had a small bottle of water with me and it was very unpleasant by the end. Definitely bring a couple liters of water; ideally in a Camelbak or similar apparatus because you’ll want to have your hands free for climbing and catching yourself from slipping.
Once you have powered through the initial hike, you will approach the first of three waterfalls. If you climb down, you can check out the pool at the bottom. Many locals and other adventurers hiking the trail bring swimming clothes and enjoy a refreshing dip to cool off from the long hike. Just don’t drink the water! If you have any open cuts or sores, you should avoid going in the water. Many of the hikes on Oahu with mountain water runoff may contain the bacteria that can give you Leptospirosis.
Once you are refreshed, you can continue along the trail by following a path to the left of the waterfall. It’s fairly easy to spot, as you should see ropes dangling down to assist you in climbing up over the waterfall. At the top of the waterfall, you will likely be tempted to lean over and take a peek or a photo. Be very careful if doing so, as many hikers have died by doing the same thing and slipped to their death.
Shortly after the first waterfall, you will encounter the second one. Once you are ready to continue, follow the trail to the right of the waterfall. This is a fairly steep climb, so use the ropes when they are available. At the top of the waterfall, you will have to hold tight against the side of the mountain and use the ropes to work your way across a narrow ledge. For those of you with a fear of heights, this is a good time not to look down.
After the ledge, there is a large boulder you will have to climb over. The other side of this boulder you will notice a small memorial plaque dedicated to one of the many hikers who have died on the trail while just trying to explore and see its beauty.
Beyond the boulder, the trail continues a little ways further until you reach the bottom of the third and final waterfall. This is a tricky waterfall. Not only are you climbing directly up this one, but it has many sharp and jagged rocks that don’t look to joyful to fall on. The waterfall itself forms almost a staircase and has four different “levels” you will have to climb over. After the first two levels, you will re-enter the woods thinking you have finished it – you have not. Once you exit the wooded area and climb over the last two levels of the waterfall, you will finally reach the bottom of the crater. From there, you have two choices: either call it a day and hike back down or push forward and see how far you can go.
If you keep going, the trail continues to the right at the top of the last waterfall. It is a fairly steep climb up the crater wall to get to the top. Personally, I have never “finished” Ka’au Crater. The rim of the crater is extremely slippery, narrow, and steep. Over half the times I’ve done the hike, the peaks of the crater have been covered in mist, making it all the more slippery. You are literally walking the ridgeline. If you slip or fall at this point, over the side you will go. The furthest I got was the second highest peak along the ridge. It was either raining or I was always too exhausted to go further than that. Remember, you still have to turn around and hike down the entire path you just came in on.
Once you do tire or decide to turn around you have two options: you can go back down the exact same way you came, which will be a magnitude more difficult than it was to climb up, or you can take the shortcut. The shortcut avoids having to climb back down all three waterfalls and will reconnect with the trail before the first waterfall. Honestly, I recommend doing both. It’s fun to climb down the waterfalls just to know how much it truly sucks. After that, take the shortcut to avoid the pain, but at least you’ll know what both experiences are like.
The shortcut starts at the top of the last waterfall, but instead of climbing up on the right side, climb up on the left. Yes, I said climb UP. Eventually that climb up with come back down through a maze of trees and berries with swarms of fruit flies. Try not to breath through your mouth or you will inhale them by the gallon.
Once you get back to the car, sit, relax, and go get some ice cream. You’ve earned it.
Elevation: 2,200 ft
Length of hike: This depends on how far you go, but if you reach the third waterfall than it’s about 5 miles round-trip. If you go beyond the last waterfall, up the crater rim, you can easily make it into a 6 or 7 mile hike. It takes between 5 and 6 hours to complete, depending on your conditioning and how far you go.
Best time to go: Any time of the day where you’ll still have daylight six hours later. The trail is shaded almost the entire route, so the sun isn’t a bother. Also, go on the driest day possible. The drier it is outside, the less slippery and muddy the trail will be.
Worst time to go: Directly after or during a rain storm. Although a little sprinkle can feel refreshing on the hike out, it doesn’t make for promising hiking conditions.