Hiking the Kaipapaʻu Pillbox Trail on Oʻahu, Hawaiʻi
Distance: 2.7 miles / 4.3 km
The Kaipapaʻu Pillbox Trail, also known as the Kaipapaʻu Bunker Trail, is one of my personal favorite Oʻahu sunrise hikes.
It’s for exactly this reason that I choose to keep it off some of my related articles, such as my 'Best Things to Do on Oʻahu' and 'Best Oʻahu Sunrise Hikes,' so that this local trail doesn’t become more popular than it should.
This aside, the Kaipapaʻu Pillbox is fairly out of the way for most hikers looking for a fun sunrise adventure, as most people from town or the east side don’t drive further north than Crouching Lion.
Kaipapaʻu Pillbox Trailhead Parking
Parking for the Kaipapaʻu Pillbox Trail is located at the very end of Kawaipuna Street in Hauʻula.
That being said, please park legally and do not block someone’s driveway.
Additionally, it will likely be difficult to remain completely quiet, as there are so many dogs in the neighborhood, but still, I kindly ask that you do whatever you can to not draw negative attention to this trailhead because local hikes need to remain local.
Google Maps Directions: Kaipapaʻu Pillbox Trailhead
Hiking the Kaipapaʻu Pillbox Trail
Initially, the Kaipapaʻu Pillbox Trail begins up this service road at the end of Kawaipuna Street before branching off on the real trail just behind the water tank.
As previously mentioned, please do what you can to be respectful in this Hauʻula neighborhood, especially because the Kaipapaʻu Trailhead is used for both the pillbox and the Kaipapaʻu Gulch Trail.
It’s here, just past the water tank, where both the gulch and Kaipapaʻu Pillbox Trail continue.
Kaipapaʻu Pillbox-Kaipapaʻu Gulch Junction
At the first clearing after the water tank, make a hard right turn up the hill to continue on the Kaipapaʻu Pillbox Trail.
The trail that continues straight is what leads deeper into Kaipapaʻu Gulch.
After the split, the Kaipapaʻu Pillbox Trail begins climbing steeply between 400-500 ft. of elevation until the top of the ridge, where the trail levels out.
There was lots of Noni when I hiked on this day, but if you don’t know, Noni is edible; however, it’s not a fruit that you want to eat.
If you notice this split in the trail, stay to the left to continue toward the pillboxes.
Almost immediately after the split, the trail will dip down into this small ravine, which is a good sign that you went the correct direction.
When the trail comes to this open erosion scar on the ridge, you can either scramble up the ridge to continue further or take the easier route and go left, which is a bit more gradual in order to get up the hill.
Kōloa Gulch-Kaipapaʻu Pillbox Junction
Had you gone left, the trail splits here, with the Kaipapaʻu Pillbox Trail continuing on the ridge to the right, as well as the loop that leads around to Kōloa Gulch.
Personally speaking, I think that it’s kind of excessive to start at the Kaipapaʻu Trailhead if your intentions were to hike Kōloa Gulch. That's why, if you’re interested, I encourage you to check out my separate Kōloa post, which has a much more direct trailhead as opposed to Kaipapaʻu.
Read My Separate Post: Kōloa Gulch Trail
After the Kōloa junction, the Kaipapaʻu Pillbox Trail levels out significantly compared to the beginning of the hike, even descending a bit to reach the two bunkers at the end.
Toward the end of the Kaipapaʻu hike, the trail will pass by the first of two bunkers, with the best one being the last, overlooking the North Shore, as shown below.
Kaipapaʻu Pillbox
From the Kaipapaʻu Pillbox, you get great views of Lāʻie and Kahuku to the north, as well as Hauʻula down to Punaluʻu to the south.
All said, making the Kaipapaʻu Pillbox a sunrise hike is more involved than most on the island, especially since it’s a little longer than comparable sunrise hikes. However, I think this is what makes Kaipapaʻu my favorite because you’re almost always guaranteed to have it to yourself. Therefore, I kindly ask that you please keep this one a secret and off social media.
To that point, posts such as this do not and never will have the same impact at exposing a place as social media does. Therefore, I wanted to create this article for the purpose of providing an accurate description of the trail, not to make a local hike more popular.
Native Plants on the Kaipapaʻu Pillbox Trail
The Kaipapaʻu Pillbox Trail is a very low-elevation Hawaiʻi hike, meaning that the vast majority of the plants you will see are non-native/ invasive species.
Nevertheless, there are a few natives that you can find on the trail, with one of the most dominant being ʻŪlei. In addition, you can expect to see ʻĀkia, ʻUhaloa, Kaunaʻoa, and if you’re lucky, you might spot an ʻŌhiʻa tree or two.
All said, if you would like to learn more about these and other native Hawaiian plants from across the islands, I encourage you to scroll through my separate post.
Read My Separate Post: Native Hawaiian Plant Guide
