In April 1925 the British explorer Colonel Percy Harrison Fawcett, aged 57, walked into the Mato Grosso region of the Brazilian Amazon with his 21-year-old son Jack and Jack’s friend Raleigh Rimell, searching for the ruins of a vanished civilisation he had named “Z.” None of the three was seen again by the outside world. Their last confirmed message was sent from a place Fawcett called Dead Horse Camp on 29 May 1925; after that the jungle closed over them. Despite decades of searches, books, expeditions and rumours, no remains, camp or grave has ever been confirmed, and the fate of the three men remains formally unresolved.
Fawcett was an experienced Royal Artillery officer turned surveyor who had mapped stretches of the Bolivia–Brazil frontier for the Royal Geographical Society from 1906 onward and had crossed the Amazon’s wilds repeatedly. By 1914 he had become convinced, partly from a colonial-era document held in Brazil’s national library (the so-called “Manuscript 512”) and partly from his own theorising, that a complex lost city — stone-built and ancient — lay undiscovered in the Mato Grosso. The 1925 expedition was his attempt to reach it, deliberately small and lightly equipped on the theory that a tiny party could move quietly and live off the land where a large one would provoke or starve.
That same theory left almost no margin and no rescue. Fawcett travelled with only his son and one young companion, swore his backers to give no relief if he failed, and pressed beyond the last point where anyone could follow. After Dead Horse Camp the record is silence broken only by Indigenous oral testimony. The most credible accounts trace the party into the territory of upper-Xingu peoples; later claims that the Kalapalo killed them were investigated and not substantiated, and forensic tests on bones once attributed to Fawcett excluded him. What is certain is that three men disappeared, and that the searches sent after them cost further lives.
Lasseter’s Reef was a fabulously rich gold reef that Lewis Harold Bell Lasseter, an Australian prospector born in Victoria in 1880, claimed to have discovered in the central Australian desert decades earlier and could lead an expedition back to. In 1930 the newly formed Central Australian Gold Exploration Company (CAGE) bankrolled a well-equipped search on the strength of his story. The reef was never found, and Lasseter died alone in the desert in late January 1931, of starvation, thirst and exhaustion, after months in which Pitjantjatjara people sheltered and fed him. The reef has never been located by anyone, before or since, and most geologists regard it as a fiction.
The CAGE expedition left Alice Springs on 21 July 1930, far better outfitted than Lasseter’s tale warranted: a heavy Thornycroft truck, a six-wheeled support vehicle, an aircraft, an established base at Ilbilba, and a party that included the leader Fred Blakeley, the prospector George Sutherland, the engineer-driver Phil Taylor, the driver Fred Colson and the pilot Errol Coote, with Lasseter as guide. Lasseter could not find his reef. He shifted his story, claimed the party was scores of miles off course, and at the Kintore–Mount Leisler country Blakeley concluded the reef was imaginary and broke off the search. The main expedition withdrew in September 1930.
Lasseter refused to give up. He pressed on into the desert with a dingo-shooter named Paul Johns and a string of camels; the two men quarrelled and parted, and then Lasseter’s two camels bolted, stranding him on foot in the Petermann Ranges with almost no food or water. He survived as long as he did only because Pitjantjatjara people of that Country took him in — they recaptured his camels for a time, gave him food including nardoo he could not digest, and built him shelter. He went blind with “sandy blight” and grew steadily weaker, recording in his diary the despair of a man who had chased millions and would have traded them all for a loaf of bread. He died near Irving Creek around 30 January 1931. The Pitjantjatjara buried him; the bushman Bob Buck found and reburied the body, and recovered the diary from a cave, in March 1931.
The Roosevelt–Rondon Scientific Expedition descended the Rio da Dúvida — the “River of Doubt,” an uncharted tributary of the Amazon in the Brazilian state of Mato Grosso — between February and April 1914, and very nearly killed the former United States president Theodore Roosevelt. It was led jointly by Roosevelt and the Brazilian army officer and explorer Colonel Cândido Mariano da Silva Rondon, who had discovered the river’s headwaters in 1909 and whose expertise, discipline and knowledge of the interior carried the party through. Of roughly twenty-two people who descended the river, three died: one paddler drowned in rapids, one camarada was murdered by another, and the killer was left behind in the forest. Roosevelt survived, gravely weakened, and never fully recovered his health.
The expedition trekked overland across the Brazilian highlands from December 1913, reaching the put-in on the River of Doubt and beginning the descent on 27 February 1914. The river proved far worse than imagined: a succession of rapids, gorges and waterfalls that forced exhausting portages, smashed and swamped the dugout canoes, and stretched a journey planned for weeks into a two-month ordeal through fever country. The camaradas — the Brazilian backwoodsmen who paddled and hauled — bore the heaviest labour. On 15 March the paddler Antônio Simplício da Silva drowned when his canoe was lost in the rapids; his body was never recovered. In early April a camarada named Julio de Lima, caught stealing food, shot and killed the foreman Manoel Vicente da Paixão; Julio fled into the jungle and was left behind.
Roosevelt himself nearly became the fourth death. On about 22 March he badly gashed his leg helping to free a canoe, the wound became infected, and malarial fever drove his temperature toward 105°F; the expedition’s physician, Dr José Antônio Cajazeira, twice operated, once lancing an abscess. Delirious and unable to walk, Roosevelt at one point asked to be left behind so as not to slow the others, and his son Kermit refused to allow it. The party reached Rondon’s pre-arranged relief at the confluence with the Aripuanã River on about 26 April 1914. Rondon renamed the river the Rio Roosevelt. Roosevelt, who had lost a quarter of his body weight, returned home broken in health and died less than five years later.