Article Presented by:
Elizabeth Jean
About 70% of the Earth's surface is permanently covered in water. Water shapes our coastlines and carves channels through countries and landscapes. Inevitably, water sometimes runs across a sudden drop in the level of the land, and a waterfall is born.
Most people can visualize a waterfall, but might find it more difficult to define. It's probably fair to say that a waterfall's defining feature is that at some point the water descends, or falls, vertically, rather than just cascading down a steep gradient.
But it is probably best not to be overly concerned with the semantics of waterfalls, but instead to appreciate the imposing spectacle they create, and the way in which they have evolved over hundreds and thousands of years.
Just as coastlines are vulnerable to erosion by water, so are river beds, hillsides and cliffs, and the fast-flowing nature of waterfalls means that over time, even the hardest rock is worn away and reshaped by the water. Two areas in particular are sure to have gradually evolved over the years - the area near the edge of the waterfall, where the water is at its fastest, and the "plunge pool" at the base of the waterfall, so-called because the riverbed has usually been worn away by the impact of the water to form an abnormally deep area.
Waterfalls are perennial tourist attractions, and many people are willing to travel considerable distances to see some of the world's most famous waterfalls in action. While aficionados and tourist authorities might like to debate the relative merits and heights of different waterfalls, the reality is that all big waterfalls have their own unique character and setting, and any large waterfall presents a truly spectacular and dramatic sight. You can add artificial waterfalls to your own backyard at http://www.garden-fountains.com.
We've taken a look at a few of the world's most famous waterfalls, to see what makes them so special.
Niagara Falls
Known by schoolchildren and adults all over the world, Niagara Falls is perhaps the most famous waterfall in the world. Straddling the border between the United States and Canada, Niagara Falls is actually made up of three falls - the Horseshoe Falls (sometimes called the Canadian Falls), the American Falls and the Bridal Veil Falls.
The landscape seen today at Niagara Falls was formed by glacial movements during the ice age. When the ice retreated and the water began to flow again, the changed landscape forced the water to carve out a new route for the Niagara River.
Niagara itself is thought to derive from the old Iroquois word for the river - Onguiaahra - "The Strait", and the Horseshoe Falls are reputed to hide the spirit of He-No, the Iroquois thunder god, who rescued his true love Lelawala as she paddled her canoe over the falls in an attempt to escape from a forced marriage. The falls are said to mask caves, where He-No and Lelawala lived together happily thereafter.
Today, Niagara Falls is split between two cities - Niagara Falls, Ontario, and Niagara Falls, New York. Both cities play host to many thousands of tourists each year, and both the Americans and Canadians benefit from the hydroelectric generation potential of the falls, each operating two hydroelectric power generation facilities that generate up to 4.4GW of power in total.
Indeed, the scale of the hydroelectric facilities is such that flow to the falls is reduced each night and throughout the summer as greater volumes of water are diverted towards the power plants, to be returned to the Niagara River downstream, below the Falls.
Niagara Falls is undoubtedly one of the world's greatest waterfall complexes, despite its relatively modest height, its exceptional width means that at peak flow more than 6 million cubic feet of water pass over its edge every minute - a true giant among waterfalls.
Victoria Falls
The widest waterfall on Earth, Victoria Falls undoubtedly ranks as one of the most spectacular waterfalls in the world. Indeed, when Scottish explorer David Livingstone first set eyes on it in November 1855, he was so impressed that he renamed the falls after his Queen, Victoria.
Known locally as the Mosi-oa-Tunya - "The Smoke That Thunders" - the falls are an amazing 1,708 meters wide, with an average drop of around 100m. In the wet season, more than 19 million cubic feet of water flow over the falls each minute, dropping down into the Zambezi Gorge below. The resulting spray, or smoke, can sometimes be seen from up to 25 miles away.
A UNESCO World Heritage site, Victoria Falls sits on the Zambezi River, dividing the African states of Zambia and Zimbabwe. Both countries have national parks named after the falls - the Mosi-oa-Tunya National Park in Zambia and the Victoria Falls National Park in Zimbabwe.
Angel Falls, Venezuela
The Angel Falls, in Venezuela, is the tallest waterfall in the world, standing a total of 3,212 feet tall. Unlike some very tall falls, water falls freely for the majority of this distance, with an uninterrupted fall of 2,648 feet.
The Angel Falls is located in the Canaima National Park, in Venezuela, and gained its name in 1937 when an adventurous American aviator, James Angel, discovered it. Although his plane became stranded upon landing in some marshy ground at the top of the falls, he and his companions made it on foot through the jungle to the nearest village and announced their discovery.
Today, tourists can take sightseeing flights over the falls, but for those who would like to see them on foot, the Angel Falls are still several days' trek through the rainforest, making it a relatively undisturbed natural marvel.
About the Author:
Written by Elizabeth Jean for http://www.Garden-Fountains.com For more information on waterfalls, visit our section on Famous Waterfalls
