One of the true natural wonders of the world, the Amazon River is an incredible stretch of water weaving through the Amazon rainforest of South America. For centuries it has been one of the most fascinating destinations for adventurous explorers in search of cities of gold or exciting rainforest vacations, yet it still remains an alluring and mystical place that hides innumerable secrets, and some astonishing facts to discover. Here are a few of our favorite fun and interesting facts about the Amazon River:
1. The Amazon is arguably the longest river in the world (if its 6,992 km measurement is to be believed), but is generally accepted as the second-longest river in the world (at 6,400 km) after the Nile (6,650 km).
2. It is the largest in terms of the quantity of water that it transports, containing more water than the Mississippi, Nile, and Yangtze combined. So much water in fact, that it delivers 55 million gallons of fresh water into the Atlantic ocean every second, or 17 billion metric tons every single day, which astonishingly equates to the amount of freshwater used by New York City every nine years! In fact it discharges more freshwater than the next seven largest rivers combined—a volume so great that it accounts for one-fifth of all the fresh water in the world’s oceans, and amazingly even a hundred miles out into the Atlantic, you could still drink the water over the side of your ship.
3. In 2006 geologists studying the speed at which the Amazon carried sediments out to sea found, to their surprise, that the oldest sediments they found were upstream of their source. They soon realized that, until the Cretaceous Period, the Amazon river actually flowed backward, east to west. It wasn’t until the Andes Mountains began their rise 100 million years ago that the river reversed course and chose its current direction.
4. The first documented European to discover the Amazon River was Spanish conquistador Vicente Yanez Pinzon in March 1500, who first detected it when he was 200 miles (300 kilometers) out to sea. He noticed that he was sailing in freshwater and turned towards the shore in search of the source, where he then found the mouth of the Amazon. He called the river “Rio Santa Maria del Mar Dulce (later shortened to “Mar Dulce”, meaning “sweet sea”).
5. Francisco de Orellana is often mistaken as the discoverer of the Amazon, as he was the first European to navigate the entire length of the Amazon River in 1541. However, he did give it its name – on two occasions, no less –firstly being called “Rio de Orellana” for a short time, before later becoming known as “Amazonas”, after his documented sightings of native female warriors who attacked his expedition and reminded him of the women warriors “the Amazons” from Hellenic culture.
6. The most distant source of the water in the Amazon River comes from melting glaciers in the mountains of Peru. For almost a century it has been agreed upon that this distant source is the headwaters of the Apurimac River on Nevado Mismi, but a 2014 study showed that the most distant source of the Amazon is on the Cordillera Rumi Cruz at the headwaters of the Mantaro River in Peru.
7. The Amazon River has the largest drainage system in the world with approximately 1,100 tributaries, 17 of which themselves are over 1,500 km long.
8. The Amazon is, without doubt, the world’s widest river. During the dry season its main channel averages 2 to 6 miles (3.2 to 9.6 km) in width, but in the wet season can reach an astonishing 30 miles (48.3 km) wide. To put that figure into perspective, if you could walk across the river it would take you about 8 hours to get from one side to the other! Its mouth is even wider, at an incredulous 235 miles (380 km)!
9. Its delta, in northern Brazil is the largest river delta on our planet, a muddy patch of salty-vs-fresh water that covers an area of roughly 1 million square miles and spans some 190 kilometers wide.
10. In 2011, the Amazon River was confirmed by scientists to have an underground version of itself 4km below it, which mirrors its above-ground twin in length, but is up to four times wider but the water therein flows much more slowly—one millimeter an hour!—through the porous sedimentary rock there. It is named the Hamza ‘River’, named after the Indian scientist leading the research group, but isn’t a river in the true sense as the water is saline at those depths.
11. The Amazon River contains the most freshwater fish species in the world, with more than 2700 species, around 1700 of which are endemic. That’s more than double the amount of species found in the Congo or Mekong rivers.
12. An entire coral reef system was discovered by researchers at the Amazon River Delta in 2016. It stretches for more than 1,000 km and covers an area of over 9,500 square kilometers. The reef is believed to be home to a unique ecosystem and a wealth of marine life. Over the last couple of years, researchers have discovered giant sea sponges ‘as heavy as a small elephant’ and an impressive collection of exotic fish, sea stars, sponges, and coral.
13. It may sound wild and untamed, but one man, Martin Skrel, conquered it all in 2007, swimming the entire length of the Amazon River. It took him 66 days and up to 10 hours of swimming per day.
14. The majority of the Amazon River has a depth of around 20 to 50 meters (66 to 164 ft) but this plunges to around 100 meters (330 ft) at its deepest points. The water levels can fluctuate enormously – Manaus in Brazil commonly sees seasonal fluctuations of between 10 and 15 meters – creating amazing zones of varzea or ‘flooded forest’. Something to consider if thinking about taking an Amazon river cruise.
15. Did you know you can surf the Amazon? Twice a year, during the biannual equinox when the sun, moon, and earth are all aligned, a natural phenomenon called the pororoca occurs, a tidal bore (wave) of incredible strength that travels inland, up the Amazon, sometimes up to 800 km from its delta. It is famous in the surfing community, with an annual championship taking place on it.
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