Hours after Japanese war planes bombed Pearl Harbor and military installations across O驶ahu on December 7, 1941, martial law fell over the Hawaiian Islands.
The military took control of the territory almost overnight. And the FBI, which had a list of suspects, began arresting people, including American citizens who had committed no crime.
Within two years, in March 1943, the largest and longest-operating of Hawai驶i鈥檚 17 known wartime detention sites opened in a remote, sweltering gulch in central O驶ahu. It closed three years later.
The prisoners who lived at Honouliuli gave it a bitter nickname: Jigoku Dani, or 鈥淗ell Valley鈥� in Japanese, for the heat that pooled, windless, at the bottom of the ravine.
This year marks 80 years since Honouliuli closed. On July 18, for the first time, the National Park Service opened its gates to the public in a pilot program. Free by a rotation of a dozen docent volunteers are held for up to 22 people once a month through the end of the year. More than 1,800 are already on the waiting list.
鈥淚 don鈥檛 want local kids growing up not knowing that this happened in Hawai驶i,鈥� said Christine Ogura, superintendent with the National Park Service, in charge of Honouliuli since 2021. 鈥淚t didn鈥檛 just happen on the mainland.鈥�
Selective Incarceration
was signed by President Franklin D. Roosevelt on February 19, 1942. It gave the military authority to remove people from designated areas of the country, and became the basis for forcibly relocating and incarcerating roughly 120,000 Japanese Americans on the West Coast and farther inland. This mainland incarceration is the story many know.
While most of the more than 2,000 Japanese Americans arrested in Hawai驶i after Pearl Harbor were shipped to camps on the continent, roughly 400 were held in Hawai驶i 鈥� first at a camp on Sand Island, and eventually at Honouliuli. The location was chosen because of its close proximity to Schofield Barracks.
By the time it closed, the 160 acres of Honouliuli had also become the territory鈥檚 largest prisoner of war camp, holding close to 4,000 people at once.
Most of those POWs were not Japanese soldiers at all, but and Okinawans who were conscripted into Japan鈥檚 imperial army, as well as Italian, German and other European Americans, who were taken on suspicion of disloyalty.
At the time, almost 40% of Hawai驶i鈥檚 population was of Japanese ancestry, so it would have been impossible to incarcerate them all. A large chunk of the labor force would have disappeared.
Instead, there was a selective choosing process: Those who were influential to Japanese communities, such as journalists, politicians and religious leaders, were taken as individuals, as opposed to families, like on the West Coast.
In total, less than 1% of those with Japanese ancestry were incarcerated in Hawai驶i during the war.
Walking a stretch of red dirt trail recently, cleared of the shoulder-high guinea grass and haole koa that once choked the path, Ogura, the superintendent, gestured at the tangle of non-native brush still crowding the slopes beyond, lined with barbed wire on the side.
Ogura is Nisei, or second generation Japanese, and grew up in Hawai驶i. She spent more than a decade working in wildlife conservation on the mainland before returning home for the job. She recalled reading about Honouliuli and realizing she had never learned this history.
鈥淚t could have been me,鈥� she said, 鈥渂ecause it鈥檚 people exactly like me 鈥� my mom, my grandparents 鈥� who were targeted.鈥�
For decades after the war, almost no trace of the camp remained visible. The army tore down the buildings when it closed Honouliuli. The site鈥檚 location was essentially lost, known only through the memories of the dwindling number of people who had lived there.
That changed in the late 1990s, when the Japanese Cultural Center of Hawai驶i began to search for the site. In 2002, working from old photographs and sketches made by the internees, they matched the terrain to a gulch in Kunia.
President Barack Obama designated Honouliuli a national monument in 2015.
鈥淲hile the treatment of Japanese Americans in Hawai鈥檌 differed from the treatment of Japanese Americans on the U.S. mainland,鈥� at the time, 鈥渢he legacy of racial prejudice, wartime hysteria and failure of political leadership during this period is common to the history of both Hawai鈥檌 and the mainland United States.鈥�
Congress designated it a National Historic Site in 2019.
鈥榃e Want Their Story To Have A Purpose鈥�
Among those who have spent years trying to keep the history of Honouliuli from disappearing again is Sharon Fujimoto-Johnson, a children鈥檚 book author, whose grandfather was incarcerated at the site. He was 29 and a U.S. citizen.
As a little girl, her father had given her a small collection of shells that his father had gathered while he was incarcerated. Those objects eventually became the seed of her illustrated book, 鈥� ,鈥� which traces his story.
When she finally visited Honouliuli in person last year with her younger daughter, she was struck by how deeply hidden the place still is.
鈥淵ou hike down, and it鈥檚 so deep down in this gulch,鈥� she said. 鈥淵ou look up and you can鈥檛 really see anything, just walls of mountain on both sides.鈥�
Standing there, she thought of her grandfather arriving with no idea when, or if, he would ever leave.
鈥淚 could feel more strongly, maybe, just a sense of despair that could have been something he felt,鈥� she said.
Her hope is that the park鈥檚 opening lets visitors reckon with the camp鈥檚 impact on many individual lives.
鈥淪o often the Japanese American incarceration is talked about in this lump sum, the story that happened to this group of people,鈥� she said. 鈥淏ut I really feel like when it鈥檚 broken down into individual stories, that hits at a different level.鈥�
Even as the first tours begin, much of Honouliuli鈥檚 physical record remains unexamined.
The tour route itself is modest for now. Beginning at the Hawai驶i Plantation Village, a shuttle sponsored by Pacific Historic Parks drives through University of Hawai驶i-West O驶ahu land before arriving at the entrance.
The trail runs down into the gulch, across the rehabilitated aqueduct, past a rock wall from the plantation days, and a low concrete slab that was once a mess hall where those incarcerated could meet visiting relatives, but only if they spoke English. The whole tour takes about 90 minutes.
A mural at UH-West O驶ahu illustrates native plants such as wiliwili, which the park hopes to someday restore at scale. For now, a few seedlings survive on their own along a rocky embankment at the site, a small sign of what native habitat once looked like before sugar cane, and later guinea grass, took over the valley floor.
Honouliuli was a part of the before James Campbell, an Irish real estate developer, purchased 41,000 acres of the ranch land in 1887.
鈥淚鈥檓 one of the many that didn鈥檛 quite know the history, especially with it being pretty much in our own backyard,鈥� said Brandon Akiona, a graduate student and docent volunteer who led the first public tour last month. 鈥淚t wasn鈥檛 really covered in school.鈥�
His own great-grandfather, he learned only recently, had been incarcerated at Sand Island, and then on the mainland.
鈥淓ssentially, the time was taken away from them for nothing,鈥� he said. 鈥淲e want their story to have a purpose and for their experiences to be heard.鈥�
At the site, tiny yellow 驶ilima flowers blossom in the foreground of a view of Pearl Harbor, which can be seen overlooking the gulch, a visual reminder of how the U.S. entered the war.
鈥淏ut what I think my park does to complement that,鈥� Ogura, the superintendent, said, 鈥渋s to show the true impact of that day on local communities.鈥�
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