The place earned the title of Hellfire Pass, for it looked, and was, like a living image of hell itself.
[Jack Chalker, Burma Railway: Images of War, London, Mercer Books, 2007, 59]
Hellfire Pass (Konyu Cutting) was the deepest and longest cutting along the entire length of the Burma-Thailand railway which over the years came to symbolise the suffering and maltreatment of Australian prisoners of the Japanese across the Asia–Pacific region.
The name 'Hellfire Pass' came from the appalling working conditions at and around this site, some 150 kilometres from the start of the railway at Nong Pladuk. In mid-1943, when the Japanese introduced a 'Speedo' to meet tight deadlines for completing the railway, prisoners were forced to work long hours into the night. Their work site was lit by oil lamps and bamboo fires. This flickering light, the noise from the drilling of the rock and the shuffling of hundreds of poorly fed prisoners seemed the very image of hell.
Work on the Konyu section of the railway was started by around 1500 British and 2000 Tamil workers from November 1942 on. Some 400 Australians from T Battalion of D Force began work in the region of Konyu Cutting close to 25 April (Anzac Day) 1943. By June work had fallen behind schedule and the Konyu area had become a bottleneck holding up work further along the railway. The Japanese brought in a further 600 prisoners including British and Australians of H Force. Around a thousand Asian labourers or rǒmusha, also worked in the vicinity of Konyu Cutting.
What is now known as 'Hellfire Pass' is a dramatic cutting some 75 metres long and 25 metres deep. The approach to this cutting consists of a longer series of excavations which created a bench on the hillside following the contour line. Whether POWs thought this too was 'Hellfire Pass' is unclear but working conditions here would have been harsh.
The excavation of these cuttings was done largely by hand, although a small number of jackhammers powered by a compressor were used. Prisoners would drill a series of small holes in the rock; one man holding a metal drill or 'tap', and another hitting its head with an 8-10 lb hammer. These drill holes would then be filled with explosive and detonated.
The resulting rubble was moved by skips running on narrow gauge lines or by hand in baskets and sacks, an exhausting and back-breaking task for hungry and ill workers.
The large workforce required to excavate Hellfire Pass, and build the bridges and embankments beyond it, was based at a network of camps below and above the railway line. Even before starting work prisoners might walk a number of kilometres up or down steep and treacherous mountain slopes.
As the line-laying parties came closer to Hellfire Pass, Japanese engineers increased the pace of work, resulting in the infamous 'Speedo' period from April to August 1943. Whereas a prisoner might previously have been expected to drill one metre per day into the solid rock, now he was made to drill two or three metres. The work day extended to fifteen, even eighteen hours. If the pace of work seemed too slow, the Japanese resorted to physical punishment.
Making conditions worse were the monsoonal rains which turned work sites and camps into quagmires and made already steep hill faces impossibly slippery.
It is difficult to know precisely how many men, Australians and others, died at Hellfire Pass itself. However, the graves in the Kanchanaburi War Cemetery show a concentration of deaths not just at Konyu and Hintok but across the length of the railway, in the period June to August 1943.
Hellfire Pass was lost to the jungle in the years after the war when the railway was demolished. But it was rediscovered in the 1980s. It is now the site of Anzac Day ceremonies and the location of the Australian government's Hellfire Pass Memorial Museum and a walking trail for visitors.