Honouliuli National Historic Site tours began last month as the National Park Service launched guided access to Oahu’s former World War II internment and prisoner of war camp in a remote Kunia gulch.
Hours after the Dec. 7, 1941 attack on Pearl Harbor, martial law was imposed across Hawaiʻi. The military quickly took control of the territory and the FBI carried out arrests of people on a suspect list, including American citizens who had not been charged with crimes.
In March 1943, the largest and longest-running of Hawaiʻi’s 17 known wartime detention sites opened in a hot, windless ravine in central Oʻahu. The camp closed three years later.
Prisoners called the site Jigoku Dani, or Hell Valley, for the suffocating heat that settled at the bottom of the gulch.
This year marks 80 years since Honouliuli shut down. On July 18, the National Park Service opened the gates to the public for the first time through a pilot program.
Honouliuli National Historic Site tours and public access
The free Honouliuli National Historic Site tours run once a month through year’s end, led by a dozen rotating volunteer docents and capped at 22 visitors per tour. More than 1,800 people are already on the waitlist, according to the park.
“I don’t want local kids growing up not knowing that this happened in Hawaiʻi,” said National Park Service Superintendent Christine Ogura, who has overseen Honouliuli since 2024. “It didn’t just happen on the mainland.”
Executive Order 9066, signed by President Franklin D. Roosevelt on Feb. 19, 1942, authorized the military to remove people from designated areas. It was used to forcibly relocate and incarcerate about 120,000 Japanese Americans on the West Coast and inland, a history more widely known on the continent.
Selective Incarceration
In Hawaiʻi, more than 2,000 Japanese Americans were arrested after Pearl Harbor, and most were sent to mainland camps. About 400, however, were held locally, first at Sand Island and later at Honouliuli, which was sited near Schofield Barracks.
By the time it closed, the 160-acre Honouliuli site had also become the territory’s largest POW camp, holding nearly 4,000 people at once.
Many POWs were not Japanese soldiers but Koreans and Okinawans conscripted into Japan’s imperial army. Others included Italian, German and other European Americans detained on suspicion of disloyalty.
With nearly 40% of Hawaiʻi’s population of Japanese ancestry at the time, mass incarceration on the scale of the mainland would have gutted the workforce. Instead, authorities targeted influential community members such as journalists, politicians and religious leaders, often detaining individuals rather than families.
In total, less than 1% of Japanese ancestry residents in Hawaiʻi were incarcerated during the war.
Ogura, a Nisei who grew up in Hawaiʻi and returned after more than a decade working in mainland wildlife conservation, said she first learned the site’s history as an adult. “It could have been me,” she said. “People like my mom and my grandparents were targeted.”
For decades after the war, almost nothing remained above ground. The Army dismantled buildings at closure, and the exact location faded from public memory.
In the late 1990s, the Japanese Cultural Center of Hawaiʻi began searching, and in 2002 researchers matched historic images and sketches to a gulch in Kunia.
President Barack Obama designated Honouliuli a national monument in 2015, noting the shared legacy of racial prejudice, wartime hysteria and failed political leadership in both Hawaiʻi and the mainland. Congress elevated it to a National Historic Site in 2019.
‘We Want Their Story To Have A Purpose’
Children’s book author Sharon Fujimoto-Johnson is among those determined to preserve Honouliuli’s history. Her grandfather, a 29-year-old U.S. citizen, was incarcerated there.
A small box of shells he collected during confinement inspired her illustrated book, “Shell Song,” about his experience.
She visited Honouliuli last year with her daughter and was struck by how hidden it remains. “You hike down and it’s so deep in this gulch,” she said. “You look up and see only the walls of the valley.”
The visit prompted her to imagine her grandfather’s uncertainty upon arrival. “I felt a sense of despair that he might have felt,” she said.
She hopes opening the park helps visitors connect with the impact on individual lives. “Often the incarceration is told as one big story,” she said. “When it is broken into personal stories, it hits differently.”
The initial tour route is modest while research continues. Visitors begin at Hawaiʻi Plantation Village, board a shuttle sponsored by Pacific Historic Parks, and travel across University of Hawaiʻi–West Oʻahu property to the site entrance.
The trail descends into the gulch, crosses a repaired aqueduct, passes a plantation-era rock wall, and reaches a low concrete slab that once supported a mess hall where incarcerated people could meet visiting relatives, but only if they spoke English. The outing lasts about 90 minutes.
On the UH–West Oʻahu campus, a mural highlights native plants like wiliwili that the park hopes to reestablish across the landscape. A few seedlings persist along a rocky bank, offering a glimpse of the native habitat that existed before sugar cane, then guinea grass, overtook the valley.
Honouliuli was once part of the island’s largest ahupuaʻa before Irish businessman James Campbell purchased 41,000 acres of ranch land in 1887.
Graduate student and docent volunteer Brandon Akiona, who led the first public tour, said he only recently learned that his great-grandfather was incarcerated at Sand Island and later sent to the mainland. “I’m one of many who didn’t know the history, even with it right in our backyard,” he said. “It wasn’t really covered in school.”
“Time was taken from them for nothing,” Akiona said. “We want their story to have a purpose and for their experiences to be heard.”
From the gulch, tiny yellow ʻilima bloom in the foreground while the view looks out toward Pearl Harbor, a reminder of the day that drew the United States into war. “What I think my park does to complement that,” Ogura said, “is show the true impact of that day on local communities.”
For more on how historical trauma and government actions continue to affect local communities, see Maui Police Department investigation raises trust concerns.
To learn more about the broader system that preserves and interprets sites like Honouliuli, visit the National Park Service.
