Hiking the ʻAikahi Pillbox (Kalāheo Hills) Trail on Oʻahu
Distance (Roundtrip): 1.0 - 2.6 miles / 1.6 - 4.2 km
The ʻAikahi Pillbox Trail, also known as the Kalāheo Hills, is a little-known secret in Kailua next to other, more popular trails, like the Lanikai Pillboxes and the Oneʻawa Hills.
That being said, hiking to the ʻAikahi Pillboxes is more difficult when compared to these similar trails, but this also depends on which route you choose to hike to the top; hence, the reason why the distance above is so variable.
With that in mind, the first route from the ʻIli ʻĀina Trailhead shown first is the easiest and most popular trail to the top. However, there are two other possible routes to the summit shown at the end, which are both less trafficked in comparison.
ʻAikahi Pillbox Trailhead Parking (ʻIli ʻĀina)
Parking for the ʻAikahi Pillbox Trail via ʻIli ʻĀina is located on ʻIli ʻĀina Street in Kailua. This is the most popular trailhead for the Kalāheo Hills.
That being said, please be quiet and respectful in this residential neighborhood, as too many trails in Hawaiʻi draw too much negative attention because people just don’t understand this.
Google Maps Directions: ʻAikahi Pillbox Trailhead (ʻIli ʻĀina)
Hiking the ʻAikahi Pillbox Trail (ʻIli ʻĀina)
Distance (One Way): 1.3 miles / 2.1 km
The ʻAikahi Pillbox Trail via ʻIli ʻĀina begins at this unmarked trailhead, which is also the same trailhead for the Kalāheo Hills BMX track.
Being the case, it’s important to pay attention to your surroundings when hiking around blind turns on the ʻIli ʻĀina route, or you risk serious injury from a collision.
Generally speaking, most of the different trails via ʻIli ʻĀina head up to the top, but if you follow the directions here, you’ll take the fastest and most straightforward route to the top.
That being said, go left at this first split.
I generally find it easiest to hike around these little jumps.
At the second split, you can follow either direction.
I chose to go right, but the trail to the left may be slightly faster to reach the same place.
At this junction, go left up the hill.
Finally, go right then right to continue up the hill, and the first lookout will be located shortly ahead.
ʻIli ʻĀina Lookout
This first open area at the top of the initial ascent is the ʻIli ʻĀina Lookout.
Here, go right to begin hiking the Kalāheo Hills toward the ʻAikahi Pillbox.
Kalāheo Hills
Upon reaching the ridge line that traverses the small peaks across the Kalāheo Hills, simply continue hiking toward the towers in the distance, where the pillbox will be found shortly beyond.
Kalāheo Hills-ʻIlimano Junction
At this first split, go left to continue along the ridge line.
That being said, the trail to the left is the route down to the ʻIlimano Trailhead, discussed later in this article.
ʻAikahi Towers
Once at the towers, follow the ridge down the stairs and up the road immediately following.
There will be a small gap on the right side of the road to continue around the fences and out to the ʻAikahi Pillbox just beyond.
ʻAikahi Pillbox (Puʻu Pāpaʻa)
After 1.3 miles (2.1 km) from the ʻIli ʻĀina Trailhead, the ʻAikahi Pillbox Trail ends at this little-known bunker lookout toward Kāneʻohe to the north, the MCBH to the east, and Kailua to the south.
Some other notable places that hikers can see from the top include Mt. Olomana, Puʻu Māʻeliʻeli, and Kualoa Ranch, to name only a few.
ʻAikahi Pillbox Trail (ʻIlimano)
Total Distance (One Way): 0.8 miles / 1.3 km
Kalāheo Hills-ʻIlimano Junction
On the way down the ʻIli ʻĀina route, I chose to go left at the Kalāheo Hills-ʻIlimano junction to hike down to the ʻIlimano Trailhead because I know it to be shorter and faster.
In comparison, the ʻIlimano route is only 0.3 miles (0.5 km) to reach this junction from the ʻIlimano Trailhead, compared to 0.9 miles (1.4 km) from ʻIli ʻĀina Trailhead.
With that in mind, the ʻIlimano route can be a good trail to hike up if you’re not interested in seeing the ʻIli ʻĀina Lookout, but know that it can be more overgrown than the traditional route.
Once at the base of the Kalāheo Hills, go left to reach the trailhead shortly ahead.
Then, it was a 0.25-mile (0.4 km) walk back to the ʻIli ʻĀina Trailhead from ʻIlimano, but I personally find the walk back on the road to be much nicer and faster than hiking back the traditional way.
ʻAikahi Pillbox Trailhead Parking (ʻIlimano)
Should you be interested in beginning from ʻIlimano, parking for the ʻAikahi Pillbox Trail is located on ʻIlimano Street in Kailua, which is the second most popular trailhead for the Kalāheo Hills.
Google Maps Directions: ʻAikahi Pillbox Trailhead (ʻIlimano)
ʻAikahi Pillbox Trail (ʻIli hau)
Compared to the first two trailheads above, the ʻIli hau Street Trailhead is my least-favorite route to hike to the ʻAikahi Pillbox, which is exactly why it’s last in this article.
I say this largely because the ʻIli hau route is more overgrown than the previous two.
ʻAikahi Pillbox Trailhead Parking (ʻIli hau)
Parking for the ʻAikahi Pillbox Trail via ʻIli hau is located on ʻIli hau Street in Kailua.
Again, this is the least-popular trailhead for the Kalāheo Hills, but for the most adventurous person, I thought that I’d include it here.
Google Maps Directions: ʻAikahi Pillbox Trailhead (ʻIli hau)
Hiking the ʻAikahi Pillbox Trail (ʻIli hau)
Distance (One Way): 0.5 miles / 0.8 km
The ʻAikahi Pillbox Trail via ʻIli hau begins at the very end of ʻIli hau Street.
Then, the trail continues around the very far side of this clearing.
At the top of the little hill in the photo above, there’s a small drainage where you will need to go left to continue on the correct trail.
Once at the water tank, you either have the option to go through the fence here or continue along the outside.
In any case, the ʻIli hau route will continue through the fence in one way or another.
ʻIlihau-Lower ʻAikahi Pillbox Junction
At this less-obvious split in the trail, you can either go right to check out the Lower ʻAikahi Pillbox or left to continue to the upper, more popular ʻAikahi Pillbox.
Back on the ʻIli hau Route
I believe the most annoying part of the ʻIli Hau route is the overgrowth after the junction when continuing to hike up to the main ʻAikahi Pillbox.
When the views begin to open up, the rest of the ʻAikahi Pillbox Trail from this point on is fairly self-explanatory.
Native Plants on the Kalāheo Hills
Since the Kalāheo Hills is a very low-elevation area by Hawaiʻi standards, native Hawaiian plants are few and far between, and the only one that stood out to me was ʻUhaloa.
If you would like to learn more about ʻUhaloa and many other native Hawaiian plants from across the islands, I encourage you to check out my separate post linked below.
Read My Separate Post: Native Hawaiian Plant Guide
