At lower water levels, more of the First Gorge can be seen
The Victoria Falls have become one of the most famous waterfalls: the sevennaturalwonders.org website ranks them as one of "Seven Natural Wonders of the World". David Livingstone, the Scottish missionary and explorer, is believed to have been the first European recorded to view the Victoria Falls — which he did from what is now known as 'Livingstone Island' in Zambia, the only land accessible in the middle of the falls. David Livingstone gave the falls the name 'Victoria Falls' in honour of his Queen, but the indigenous name of 'Mosi-oa-Tunya' — literally meaning the 'Smoke that Thunders' — is also well known. The World Heritage List recognizes both names. While it is neither the highest nor the widest waterfall in the world, it is claimed to be the largest. This claim is based on a width of 1,708 metres (5,604 ft) and height of 108 metres (354 ft), forming the largest sheet of falling water in the world. The falls' maximum flow rate compares well with that of other major waterfalls (see table below).
For a considerable distance upstream from 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 transverse chasm 1708 meters (5604 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 metres (260 ft) at its western end to 108 metres (354 ft) in the centre. The only outlet to the First Gorge is a 110 metres (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 — the place that David Livingstone first saw the falls from in Zambia. At less than full flood, additional islets divide the curtain of water into separate parallel streams. The main streams are named, in order from Zimbabwe (west) to Zambia (east): Devil's Cataract (called Leaping Water by some), Main Falls, Rainbow Falls (the highest) and the Eastern Cataract
‘The Smoke that Thunders’, rainy season, 1972 ... and dry season, September 2003
Size and flow rate of Victoria Falls with Niagara and Iguazu for comparison
Parameters Victoria Falls Niagara Falls Iguazu Falls
Height in meters and feet: 108m 360 ft 51 m 167 ft 64–82 m 210–269 ft
Width in meters and feet: 1,708 m 5,604 ft 1,203 m 3,947 ft 2,700 m 8,858 ft
Flow rate units (vol/s): m³/s cu ft/s m³/s cu ft/s m³/s cu ft/s
Mean annual flow rate: 1,088 38,430 2,407 85,000 1,746 61,600
Mean monthly flow — max: 3,000 105,944
— min: 300 10,594
— 10yr max: 6,000 211,888
Highest recorded flow: 12,800 452,000 6,800 240,000 12,600 444,965
Notes: See references for explanation of measurements.
For water, cubic metres per second = tonnes per second.
Half the water approaching Niagara is diverted for hydroelectric power.
Iguazu has two drops; height given for biggest drop and total height.
10 falls have greater or equal flow rates, but are not as high as Iguazu and Victoria Falls.
The Zambezi basin above the falls experiences a rainy season from late November to early April, and a dry season the rest of the year. The river's annual flood season is February to May with a peak in April, The spray from the falls typically rises to a height of over 400 metres (1,300 ft), and sometimes even twice as high, and is visible from up to 50 km (30 miles) away. At full moon, a "moonbow" can be seen in the spray instead of the usual daylight rainbow. During the flood season, however, it is impossible to see the foot of the falls and most of its face, and the walks along the cliff opposite it are in a constant shower and shrouded in mist. Close to the edge of the cliff, spray shoots upward like inverted rain, especially at Zambia's Knife-Edge Bridge. As the dry season takes effect, the islets on the crest become wider and more numerous, and in September to January up to half of the rocky face of the falls may become dry and the bottom of the First Gorge can be seen along most of its length. At this time it becomes possible (though not necessarily safe) to walk across some stretches of the river at the crest. It is also possible to walk to the bottom of the First Gorge at the Zimbabwean side. The minimum flow, which occurs in November, is around a tenth of the April figure; this variation in flow is greater than that of other major falls, and causes Victoria Falls' annual average flow rate to be lower than might be expected based on the maximum flow.
Victoria Falls is roughly twice the height of North America's Niagara Falls and well over twice the width of its Horseshoe Falls. In height and width Victoria Falls is rivalled only by South America's Iguazu Falls. See table for comparisons.