During World War II, the U.S. Army Corps of Engineers constructed numerous pillboxes across Oahu. These concrete bunkers served as coastal defense structures strategically positioned to monitor and protect against potential invasions following the attack on Pearl Harbor.
Today, these pillboxes have been repurposed as hiking destinations, offering historical insight and breathtaking vistas. Hikers can explore these remnants of military history while enjoying the natural beauty of Oahu’s diverse landscapes.
As a history buff and hiker, I’ve always been intrigued by the remnants of World War II scattered across Oahu’s landscape. Recently, I decided to explore some of these former lookouts.
The Lanikai Pillboxes, known as the Kaiwa Ridge Trail, are among Oahu’s most popular hikes. Initially, these bunkers were built to spot enemy ships approaching from the Pacific Ocean, especially after the bombing of Pearl Harbor. Today, the pillboxes offer hikers a stunning view of the sunrise. However, increased foot traffic has led to erosion concerns, prompting trail maintenance and preservation discussions.
Waking up before dawn and hiking in the still darkness to the Lanikai Pillboxes was an unforgettable experience. The sky was filled with incredible colors as the sun slowly rose behind the Mokulua Islands. It feels like watching a whole new world unfold before your eyes. The cool morning breeze and sweeping views made me feel small in the face of the beauty of nature and history.
May 2025 Update: The Kaiwa Ridge trail continues to experience erosion pressure due to its popularity. Local authorities have implemented additional maintenance measures. Hikers should stay on designated trails and avoid stepping on vegetation off-trail. Some hikers have recently reported an increase in flies in the morning, so bringing bug spray may be helpful.
The Maili Pillbox, affectionately known as the Pink Pillbox, stands out for its vibrant hue. The pink color was initially used to raise breast cancer awareness and has since become a symbol of community support. The trail offers sweeping views of Oahu’s western shores.
The bright pink of the Maili pillboxes immediately caught my eye. Climbing under the hot Leeward Oahu sun, I felt the contrast between the cheerful color and the building’s past. I could even spot some new graffiti—impromptu artwork from hikers coming and going. The views of the Waianae coastline from the top were stunning, and I spent a few moments inside the pillbox, imagining how the sentries used to watch over the ocean. They must have felt isolated, yet incredibly important.
Nestled amidst lush vegetation, the Ehukai Pillboxes provide hikers a serene journey through tropical flora. The trail culminates in pillboxes overlooking the famed North Shore surf breaks, offering a unique vantage point of Oahu’s surfing culture.
Hiking the Ehukai trail feels like stepping into another world. The sound of waves from Sunset Beach accompanies every step. The humid air and the scent of damp leaves are incredibly refreshing. Once you reach the pillbox, the view of the Pacific Ocean is breathtaking. I could see tiny surfers in the distance, riding the legendary waves. It feels like discovering a hidden treasure deep in the forest.
Diamond Head, also known as Leahi, is a volcanic tuff cone that houses several World War II-era bunkers. The trail to the summit includes steep stairways and tunnels that lead to observation posts with sweeping views of Honolulu. Diamond Head offers geological and military history as a registered historic site.
Diamond Head is more than just a hike—it’s a living history lesson. The bunkers here aren’t just ordinary lookout points; they were part of an advanced coastal defense system, often housing large artillery capable of firing out to sea. Climbing the narrow stairs and passing through the dark tunnels is a truly immersive experience. I could feel the chill of the old concrete walls and imagine the soldiers who once stood guard there, far from the cheers of the city now visible below. The view of Waikiki from the top—with its hotels and beaches—stands in striking contrast to its military past.
Koko Head Crater Trail challenges hikers with a steep climb of 1,048 steps, originally part of a military tramway. This grueling hike rewards you with sweeping views of Hanauma Bay and the southeastern coastline.
Climbing the 1,048 steps of Koko Head tested my physical endurance. Sweat poured down, and my muscles burned. I had to stop several times to catch my breath, but I saw the summit every time I looked up and kept pushing forward. Every step was worth it when I finally reached the top and was greeted with an incredible 360-degree view. Feeling the wind on my face after such a strenuous climb was priceless. I could even see the remnants of artillery platforms and other observation structures near the summit—a powerful reminder of its vital role during the war.
Puʻu Maʻeliʻeli offers a relaxed hike that’s perfect for families and beginners.
The trail winds through lush forest, leading to a pillbox that provides stunning views of Kaneohe Bay and the Koʻolau Mountains.
Puʻu Maʻeliʻeli is a pleasant surprise.
I was looking for something less challenging after Koko Head, and this trail was just right. The air is fresh, filled with the scent of native plants, and the sound of birds creates a calming soundtrack. The pillbox here might not be as iconic as others, but its hidden location among the trees gives it a mysterious vibe. The view of Kaneohe Bay from the top is breathtaking. Kids would enjoy this little adventure, imagining where the “guardians” once hid.
Kaʻena Point is a protected Natural Area Reserve, home to native Hawaiian flora and fauna. The trail follows an old railway bed, leading to a secluded coastline where hikers may encounter endangered monk seals and nesting seabirds.
The Makapuʻu Point Lighthouse Trail offers an accessible hike with stunning ocean views. During the winter months, hikers can spot humpback whales breaching offshore. The trail ends at a historic lighthouse perched atop sea cliffs.
The Crouching Lion Trail is a brief but steep ascent to a pillbox overlooking Kahana Bay. It is less frequented, offering a more secluded experience for hikers seeking solitude and sweeping vistas.
This trail is near Turtle Bay Resort and provides a leisurely hike to a coastal pillbox. It is well-maintained and family-friendly, making it ideal for those seeking a relaxed outdoor activity.
The Haiku Stairs, also known as the “Stairway to Heaven, ” is a steep trail with 3,922 steps ascending the Koʻolau Mountains. Originally built during WWII for access to a radio station, the trail has been closed to the public since 1987 due to safety concerns. Despite its closure, unauthorized hikers continue to access the trail, leading to legal issues and safety hazards. In 2024, the city initiated the removal of the stairs to prevent further trespassing and accidents.
Battery Cooper is a WWII-era coastal defense installation located within Kualoa Ranch. The site has been preserved and integrated into the ranch’s movie tour, showcasing its historical significance and cinematic appeal. Visitors can explore the bunkers and learn about their role in Hawaii’s military history.
For a visual guide to these trails, refer to the interactive map below, which highlights the locations and provides directions to each pillbox hike.
| Hike Name | Location | Distance (Round Trip) | Difficulty | View Highlight |
|---|---|---|---|---|
| Lanikai Pillboxes | Kailua (Windward) | ~1.8 miles | Moderate | Sunrise over Mokulua Islands |
| Maili (Pink Pillbox) | Waianae (Leeward) | ~1.6 miles | Moderate | Ocean & west shore sunset views |
| Ehukai Pillboxes | North Shore | ~2.3 miles | Moderate | Surf breaks at Banzai Pipeline |
| Diamond Head | Honolulu | ~1.6 miles | Easy | Crater, Waikiki skyline, & Pacific views |
| Koko Head Crater | East Oahu | ~1.8 miles (1,048 steps) | Difficult | 360° views from summit |
| Puʻu Maʻeliʻeli | Kāneʻohe | ~2.0 miles | Easy-Moderate | Peaceful jungle trail, Kāneʻohe Bay views |
| Kaʻena Point | Northwest Oahu | ~5.0 miles | Easy | Wildlife refuge, tide pools, & open coast |
| Makapuʻu Pillboxes | East Oahu | ~2.0 miles | Moderate | Whale-watching outlook over ocean cliffs |
| Crouching Lion | Kahana (Windward) | ~1.5 miles | Difficult | Dramatic cliffs, Koʻolau range views |
| Turtle Bay Pillbox | North Shore | ~1.2 miles | Easy | Ocean-side walk, beginner-friendly trail |
| Haiku Stairs (Bonus) | Kāneʻohe | ~3.0 miles (illegal entry) | Extreme | Stairway to Heaven, panoramic island views |
| Battery Cooper (Bonus) | Kualoa Ranch | Guided access only | Easy (Tour-based) | Jurassic filming site, preserved bunkers |
Exploring WWII pillbox hikes in Oahu is more than just a physical activity—a journey through history, culture, and nature. Whether you’re a history buff, nature lover, or just looking for Instagram-worthy views, these trails offer something for everyone.
From the vibrant graffiti of the Pink Pillbox to the windswept views atop Lanikai, each site tells a story about Oahu’s role in World War II and how nature has reclaimed these wartime remnants. Respect the trails, preserve their legacy, and enjoy the breathtaking scenery that makes hiking in Hawaii truly unforgettable.
Exploring Oahu’s former World War II lookout posts is more than a hike. It’s a journey through time, a chance to reflect on history, and a way to marvel at how nature has reclaimed remnants of the past. Each pillbox has a story to tell, and the experience of climbing them has left a lasting impression on me.
Bonnie May is a seasoned journalist and passionate travel writer with a deep love for storytelling and discovery. With years of experience reporting on diverse cultures, hidden destinations, and unforgettable experiences, Bonnie brings the world to her readers through vivid narratives and thoughtful insight. When she’s not on the road, she shares travel tips, local food finds, and inspiring stories that make you want to pack your bags and explore.
