Surviving a rebel attack and braving crocodile-infested waters, a group of explorers - including two New Zealanders - has completed an 80-day voyage up the world's longest river reaching what they say is the source of the Nile.
The three explorers from Britain and New Zealand claim to be the first to have travelled the river from its mouth to its "true source" deep in Rwanda's lush Nyungwe rainforest.
"History has been rewritten," British explorer Neil McGrigor told reporters.
"This is the end of an 80 day amazing and exhausting journey."
The expedition, dubbed "Ascend the Nile", travelled over 6700 kilometres in three boats, tracing the Nile from the Mediterranean through five countries to what they say is its origin.
McGrigor and New Zealanders Cam McLeay and Garth MacIntyre suffered a rebel attack in northern Uganda, which killed one of their team, and overcame a cocktail of testing climates, massive rapids and crocodile charges before reaching their final destination.
The last leg of their journey saw them abandon their tiny boats and trek some 70km for seven days through thick forest, sometimes being forced to wade in the fast-running Nile waters.
"We have followed the Akagera River system to its longest point up in the Nyungwe forest and it's this point that we now finally know as being the longest source of the river Nile," McGrigor told Reuters.
The team, which used a Global Positioning System (GPS) and inflatable motorboats, believes the Nile is at least 107km longer than previously thought.
Debate over the real source of the Nile has raged since the late 1850s, when British explorers like John Hanning Speke began staking their reputations, fortunes and health on finding it.
It was not until the 1864 expedition by American journalist Henry Stanley - when he found missing Briton David Livingstone in 1871 and circumnavigated Lake Victoria and Lake Tanganyika for the first time - that much of the area was mapped and many questions answered.
But not all experts were convinced by the team's discovery.
"Their claim to have found a new source for the Nile just depends on what counts as a meaningful source," Pasquale Scatturo, who documented his descent of the Blue Nile in the IMAX film Mystery of the Nile, was quoted by National Geographic's website as saying.
Robert Collins, author of the book The Nile, was quoted by National Geographic as saying: "They're talking about a difference of a few miles. ... These chaps are really just out for adventure, and I'm all for that."