The Japanese military chose a cutting over a tunnel for one coldly practical reason: a tunnel could only be worked from two ends simultaneously, while a cutting could be attacked from every point along its length. Speed mattered more than the lives it would cost. The Burma Railway, stretching from Bangkok to Rangoon, was a strategic lifeline intended to supply Japanese forces in Burma without relying on vulnerable sea routes. Hellfire Pass was its largest and most difficult rock cutting, located in a remote stretch of the Tenasserim Hills where proper construction tools were essentially nonexistent. Australian, British, and Dutch prisoners of war, along with tens of thousands of Southeast Asian civilian laborers, did the work with hand drills, hammers, and dynamite. Sixty-nine men were beaten to death by guards during the six weeks of construction. Many more died of cholera, dysentery, starvation, and sheer exhaustion. The civilian laborers, mostly Malayans of Chinese, Malay, and Tamil descent who had been lured with false promises of good jobs, suffered the same brutality as the prisoners of war.

Just past Hellfire Pass lay Hintok, where the railway began its climb into the highlands. Four camps housed the workers: a river camp subdivided into British, Australian, and Tamil sections, and a mountain camp holding Australian, British, and Dutch prisoners under the command of the legendary surgeon Colonel Weary Dunlop. A bamboo fence surrounded the mountain camp, not to keep prisoners in, but to keep tigers out. The first prisoners arrived on 26 January 1943 and immediately began clearing forest and building the camps that would confine them. By March, eight hundred men labored there. They built a 400-meter-long trestle bridge that collapsed three times during construction, earning the darkly apt nickname 'the Pack of Cards Bridge.' On 19 June 1943, cholera swept through the mountain camp, killing 57 Australian prisoners. Another 31 died in the bridge collapses, and 29 more from guard brutality. The Three-Tiered Bridge, frequently photographed after the war, has since been reclaimed by the jungle.

The preservation of Hellfire Pass began with one man's refusal to let it be forgotten. In 1983, J.G. 'Tom' Morris, a former prisoner of war, returned to Thailand and resolved that portions of the Death Railway should be preserved as a historical site. His advocacy led the Australian government to commission the Snowy Mountains Engineering Corporation in 1984 to survey the railway and identify a suitable location. Jim Appleby, an engineer stationed at the nearby Khao Laem dam, conducted much of the groundwork and forwarded his reports to the Australian-Thai Chamber of Commerce in 1985. The first dawn service was held at Hellfire Pass on Anzac Day 1990, a tradition that continues to this day. The memorial museum that followed, co-sponsored by the Royal Thai Armed Forces Development Command and the Australian government, was built by the Office of Australian War Graves and opened by Prime Minister John Howard.

Renovated in 2018, the Hellfire Pass Interpretive Centre now offers visitors something no textbook can replicate: the chance to walk through the cutting itself. The rock walls still bear the marks of hand drills and dynamite. An audio tour, featuring the recorded memories of surviving prisoners of war, accompanies visitors along a section of the former railway track bed. Multimedia displays and artifacts fill the museum, but the cutting is the experience that stays with people. Standing at the bottom of a 25-meter rock corridor, knowing it was carved by starving men working through the night, creates a physical understanding of what happened here that words and photographs cannot fully convey. The nearest town and tourist base is Kanchanaburi, where visitors can take the State Railway of Thailand over the Wang Pho Viaduct and across the bridge over the River Kwai. No trains run through Hellfire Pass anymore. After the war, the railway was never rebuilt to a lasting standard, and the line now terminates at Nam Tok Sai Yok Noi.

More than 250,000 Southeast Asian civilians and 12,000 Allied soldiers built the Burma Railway. The death toll among civilian laborers, who had no military organization to document their losses and no governments to advocate for their memory, remains imprecise and almost certainly undercounted. Hellfire Pass is one point on a 415-kilometer line of suffering, but it has become the place where that suffering is most viscerally remembered. The Australian and New Zealand flags left by visitors at the memorial, the shrine at the site, the dawn services on Anzac Day, all these gestures of remembrance point toward something that the raw statistics of death tolls and construction timelines cannot contain: the individual human experiences of the people who were forced to cut through this mountain, and who died doing it.