Seven Natural wonders of the world
Seven Natural wonders of the world : Grand
Canyon | Great
Barrier Reef | Harbor
of Rio de Janeiro | Mount
Everest | Polar Aurora
| Paricutin volcano | Victoria
Falls
Victoria Falls
Africa's Victoria Falls or Mosi-oa-Tunya are, by some measures, the largest waterfall on the planet, as well as being among the most unusual in form, and having arguably the most diverse and easily-seen wildlife of any major waterfall site.
Physical features
For a considerable distance above the falls, the Zambezi flows over a level sheet of basalt, in a shallow valley bounded by low and distant sandstone hills. The river's course is dotted with numerous tree-covered islands, which increase in number as the river approaches the falls. There are no mountains, escarpments, or deep valleys which might be expected to create a waterfall, only flat plateau extending hundreds of kilometres in all directions.
The falls are formed as the full width of the river plummets in a single vertical drop into a chasm 60–120 m (200–400 ft) wide, carved by its waters along a fracture zone in the basalt plateau. The depth of the chasm, called the First Gorge, varies from 80 m (262 ft) at its western end to 108 m (360 ft) in the centre. The only outlet to the First Gorge is a 110 m (360 ft) wide gap about two-thirds of the way across the width of the falls from the western end, through which the whole volume of the river pours into the Victoria Falls gorges.
There are two islands on the crest of the falls that are large enough to divide the curtain of water even at full flood: Boaruka Island (or Cataract Island) near the western bank, and Livingstone Island near the middle. At less than full flood, additional islets divide the curtain of water into separate parallel streams. The main streams are named, in order from from Zimbabwe (west) to Zambia (east): Leaping Water (called Devil's Cataract by some), Main Falls, Rainbow Falls (the highest) and the Eastern Cataract
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