There has been a healthy academic debate over the world's longest river for some years and the claim from Brazil may not go unchallenged.

BBC: NEWS | Americas | Amazon river 'longer than Nile'

Guido Gelli, director of science at the Brazilian Institute of Geography and Statistics, told the Brazilian network TV Globo that today it could already be considered as a fact that the Amazon was the longest river in the world.

BBC: NEWS | Americas | Amazon river 'longer than Nile'

The Missouri is the longest river.

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The archive is thought to be the longest for any river in the world.

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While the exact location has yet to be confirmed from two choices, scientists say either would make the river the longest in the world.

BBC: NEWS | Americas | Amazon river 'longer than Nile'

An 1836 map of the city shows several large islands in the middle of the river, Michigan's longest running 232 miles from the center of the state west to Lake Michigan.

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The Yellow River, China's second longest, has dried up since the early 1970s.

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The Yellow River, one of the world's longest, supplies water to more than 150 million people and 15 percent of China's agricultural land.

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