The definition of a natural wonder is that it must clearly be a natural site or monument that was not made by or altered by humans. All seven of this original list are still in existence today and remind us to protect and care for these and all other natural places on the planet.  

The seven wonders of the natural world are:

©Getty Images

©Getty Images

Mount Everest

It is the highest spot in the world, at 8,848 m high.

It is one of the Himalaya mountains, between Nepal and Tibet, and is over 60 million years old. Movement of tectonic plates pushes the Himalayas, including Mt Everest, higher each year by up to 4 cm. The summit, or top, of Everest is covered in deep snow all year round, winds can reach over 321 kph, and the temperature can be minus 62ºC.

On 29 May 1953, Sir Edmund Hillary and Tenzing Norgay, a Nepalese Sherpa, were the first to reach the summit.

Part of the Grand Canyon ©Getty Images

Part of the Grand Canyon ©Getty Images

The Grand Canyon

The Grand Canyon in Arizona, southwestern USA, was carved by the Colorado River and its tributaries (smaller rivers that feed into a main river) over many centuries, possibly 17 million years. The Canyon and its many caves have been continuously inhabited by Native Americans for thousands of years. It is up to 1800 m deep, about 446 m long and between 6.4 to 29 km wide.

©Getty Images

©Getty Images

Polar auroras

These are amazing light shows of dancing waves of colours in the sky near the two magnetic poles. The aurora borealis, or Northern Lights, are the most spectacular, but there is a southern aurora (aurora australis) in the southern hemisphere near the south magnetic pole. Their appearance cannot be predicted. They are the result of atoms being ionized, or excited, by solar wind particles speeding along the lines of Earth's magnetic fields.

The Harbour at Rio de Janeiro

©Getty Images

©Getty Images

The Harbour was created by erosion from the Altantic Ocean. It is the largest natural deep water bay in the world. It is surrounded by mountains, including Mt Sugar Loaf (over 395 m), Corcovado Peak (705m) and the Hills of Tijuca (1,020m). The famous statue of Christ the Redeemer, one of the seven wonders of the modern world, stands on the top of Corcovado.

A clown fish in the Great Barrier Reef. ©Getty Images

A clown fish in the Great Barrier Reef. ©Getty Images

The Great Barrier Reef

The Great Barrier Reef is the largest coral reef in the world, located in the Coral Sea off the coast of Queensland in Australia. It is over two and a half km long, consisting of a chain of over 2,900 separate reefs. Coral is made by millions of tiny carnivorous animals called polyps. The Great Barrier Reef can be seen from space. It is habitat to many vulnerable or endangered animals, some of which are found nowhere else in the world. This includes 30 kinds of whales, dolphins and porpoises; 6 kinds of sea turtle; 125 different sharks and members of the stingray family; hundreds of fish species, as well as frogs, seahorses and sea snakes. There are 400 kinds of corals and 15 kinds of sea grass.

The volcano is now extinct. ©Getty Images

The volcano is now extinct. ©Getty Images

Paricutin Volcano

It is a cinder cone volcano in Mexico and last erupted in 1952. It is included in this list because it is unique among volcanoes... it was observed from its beginning until its end. In its first year, it grew to a height three quarters of what it is now. Two weeks before its sudden appearance, villagers of Paricutin heard rumblings and felt the earth shake. On the night of 20 February 1943, a farmer found a mound of hot soil in his cornfield. It suddenly rose 2 m high, and released ash and fumes into the air. Within one day, the volcano had grown to 50m high, and extremely hot gases were exploding from the vent. Five days later, lava began flowing from the vent and over the surrounding area, moving at a speed of 60m a minute. The first year of its existence was the most active, and it grew to 330m high, with a cloud of ash over 8km high. Ash fell 300km away. Eruption was continuous until 1952. It is now classified as an extinct volcano. It is now 3,170 m high.

©Getty Images

©Getty Images

Victoria Falls

These are the largest waterfalls in the world, based on width and height: 1,609 km wide and almost 110m high, and are the most spectacular.

This part of the Zambezi River is over 2 km wide as it flows over a series of ancient basalt cliffs. The African name, Mosi-oa-Tunya, means 'mist that thunders' because the spray from the falling water rises almost 400 m in the air and can be seen over 20 km away. The national border between Zambia and Zimbabwe is the centre of the Zambezi River, so the falls are in the national parks of both countries.

Learn more about the wonders of the world:

Watch a video of the Great Barrier Reef

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