The Nile is famous for being the longest river in the world; however, it is outranked by another for its extraordinary water flow. Nestled in the northern portion of South America is the Amazon River.

Measuring 4,000 miles (6,400 kilometres), it is slightly shorter than the Nile but is the equivalent of the distance from New York City to Rome, reported Britannica. The Amazon River passes through Brazil, Columbia, Peru, and Venezuela, but Brazil holds the largest portion. Also known as the Solimões River, famously meets with the Rio Negro River to form the Amazon River's main channel.

For six kilometres, the two rivers run next to each other without mixing, creating a beautifully contrasted landscape of half-pale sandy water and dark black water.

Where the Amazon River starts has been a topic of debate for centuries. Its western source is located in the Andes Mountains, just 100 miles from the Pacific Ocean.

Its mouth lies on the northeastern coast of Brazil, in the Atlantic Ocean. The mouth of the Amazon River is approximately 202 miles wide, almost the same distance between London and Paris (212.98 miles).

The river carries the largest volume of freshwater in the world, and according to the Earth Observatory, this accounts for nearly 20 per cent of the Earth's discharge into the oceans.

The Amazon River discharges approximately 200,000 litres of freshwater into the ocean every second. In fact, it releases so much freshwater into the Atlantic that it impacts the sea level in the Caribbean.

"On average, models predict the Amazon River alone causes sea levels around the Caribbean to be around 3 cm higher than they would be without the Amazon's freshwater contributions," reported Treehugger. 

The astonishing river is also known for its incredible and unique aquatic and semi-aquatic animals, such as the Electric Eel, the Arapaima fish, the Green Anaconda, the Piranha fish and the Black Caiman. 

However, it is most known for having the Amazon River dolphin.

"These dolphins are noted for the pink colour of adults, which is more prominent in males," writes the World Atlas. The Amazon River dolphin can weigh as much as 185 kg and grow as long as 2.5 metres. 

Another unique aspect of the Amazon River dolphin is their ability to turn their necks from side to side, which other dolphins cannot do.

Despite its size, no bridges allow locals to cross either side. Around 10 million people live on the banks of the Amazon River, which they can only cross by boat.

The rainy seasons can rise over the river by "30 feet, tripling the width of the River in some places," reported the TreeHugger. 

"The Amazon's soft river banks erode with the seasonal inundation of rainwater, making previously sturdy areas into unstable floodplains," leaving locals to travel by boat.