NAM TOK, Thailand — Wielding a machete, Rod Beattie slashes at tangled undergrowth and soaring bamboo to expose vistas from one of World War II's iconic sagas. Out of the jungle appear remnants of a railway that cost the lives of more than 100,000 Allied prisoners and Asians enslaved by Japan's Imperial Army.
As the 70th anniversary of the war's end approaches and its veterans dwindle by the day, the aging Australian still slogs along the 415-kilometer (257-mile) length of "Death Railway." With his own money, he maps its vanishing course, uncovers POW relics and with his vast database helps brings closure to relatives of the dead — not only those who perished building the railway, but also those who went to their graves never having shared their traumas.
Beattie acknowledges to being a man obsessed.
"The life I have given isn't just for them but for their descendants," he says. "Their children are now at an age where they have retired. They've got time to ask questions — 'Where was my father? What happened to him?'" And many, bringing along their own children and even grandchildren, are making what Beattie calls pilgrimages to the railway to seek answers, find peace and shed tears.
One daughter he escorted was able to learn for the first time exactly where her father, Pvt. Jack McCarthy, died on July 21, 1943, of what diseases and where he was initially buried.
"It made her very happy," Beattie said.
Arguably the world's authority on this drama of inhumanity and courage in a green hell, this one-man band has also busted myths and plain inaccuracies that have accumulated around the railway. Some are drawn from a still-ongoing parade of memoirs, novels and films, from the classic 1957 movie classic "The Bridge on the River Kwai" to "The Railway Man" in 2013 and "The Narrow Road to the Deep North," a novel that won Britain's top literary prize last year.
He's driven, he says, "for history's sake. To give people a true version of the story. After I leave or pass away, who would otherwise know where the railway was?"
Beattie, 67, clambers down a steep slope where the track has been replaced by a rolling field of tapioca. Within 15 minutes, aided by a metal detector and pickax, he uncovered 11 relics under the reddish soil, including railway staples and bolts. He also gathered clues to the location of a labor camp, Tampii South, that he has yet to pinpoint.
Tampii South was among a string of POW camps along the railway, which the Japanese regarded as a strategic supply line from Japanese-controlled Thailand to their forces in Myanmar as Allied warships made the sea route around the Malay Peninsula increasingly hazardous. Completed in 15 months, the railway was an incredible feat of engineering and human toil.
More than 12,000 Australian, British, Dutch and American prisoners died along with an estimated 90,000 Asians, including Tamils from Malaysia, Burmese and Indonesians — some 250 corpses for every kilometer of track. Working with primitive tools and their bare hands, the prisoners succumbed to cholera, beriberi, starvation, executions and despair.
A civil engineer in Australia, Beattie arrived in Thailand in 1990 to work as a consultant in the gems industry. He settled in the western Thailand town of Kanchanaburi, a key railway terminus and site of the infamous bridge on the River Kwai. His passion was kindled by the history around him and his own background: two of his uncles had been killed and his father twice wounded in World War II. Beattie himself served in the Australian military for six years.
In the mid-1990s, with machetes and chain saws, he and his Vietnamese wife, Thuy, eight months pregnant, cleared 4.5 kilometers (2 miles) of rail bed at a rock cutting known as Hellfire Pass, paving the way for a memorial and museum there. In 2003, he opened the Thailand-Burma Railway Center in Kanchanaburi, both a research facility and a superb museum incorporating some of the thousands of artifacts he had uncovered.
Although Japanese atrocities are graphically depicted, it is not a mere museum of horrors. Japanese soldiers also suffered hardships and savage commanders, and not all are portrayed as brutes. The exhibits include rare photographs provided by a Japanese engineer on the railway.
Beattie has corrected misconceptions about the railway that had made it into a number of history books, including some that flatly state that Japanese guards killed 68 Australian POWs at Hellfire Pass. He proved that the guards killed no Australians there by going through a database of 105,000 records of nearly every prisoner in Southeast Asia.
Beattie found that Allied POW records were so sketchy that some relatives even had false information about where their fathers died. He said the index cards that Japan's Imperial Army kept on every POW sometimes have proved more helpful than Australian officialdom. He also dug into archives around the world including hospital and burial records, cemetery maps, regimental documents and diaries to reconstruct the tortured odysseys of thousands. He offers them to any who want to know, and has received decorations from Australia, the Netherlands and Great Britain for his work.
Beattie's ongoing work includes a detailed GPS mapping of the entire rail line that in Thailand is 60 percent completed. Earlier, logging more than 3,000 kilometers (1,860 miles) on foot, he plotted the Thai end and some of the Myanmar stretch on a 1:50,000 map.
"Probably when I die," he says when asked when he'll halt his self-imposed mission.
Beattie's labors seem a race against the clock: The railway is vanishing along with those who built it.
But earlier in the year, 34 Australians, mostly children of POWs, gathered at the main Allied cemetery in Kanchanaburi town for a simple, moving service among the 6,982 graves. Some wore the medals of fathers they never knew: They were conceived before their fathers left for war or were simply too young to remember them. They sought information from Beattie.
It was the first trip to the River Kwai for Elizabeth Pietsch, whose father died in 2013 at the age of 95.
"He never talked about it very much, but when he did, tears would well up in his eyes," she said. "He went on to be a chartered accountant, a very successful man, but it was always there, the elephant in the room... It was the defining time of his life."
Cemetery with museum in background...no Americans buried here. 

Square center sections were replaced after allied bombing.

Walking across the bridge...it's now a tourist railroad from Bangkok.