Makgadikgadi pan is one of the largest salt flats in the world covering approximately 16,000 sq km. The pans are the dried out remains of a huge superlake which covered most of central Botswana several millions of years ago. Climate change, earthquakes and the diversion of rivers starved this lake of its water supply, causing it to shrink and disappear into flat depressions of grey clay and salt.
Makgadikgadi pan is featureless save for a few isolated outcrops of igneous rock that extrude from the surface of the pans, notably Kubu Island in the west. After good summer rains the salt flats are transformed into shimmering shallow lakes, giving a glimpse of what the great superlake must once have been like. Sometimes when rains are heavy, the pans gets additional water from as many as five seasonal rivers. This attracts vast number of pelican and millions of flamingos to this corner of Makgadigadi.
Evidence of the former lake exists in the form of fossil pebble beaches along the shore of Kubu Island and other granite outcrops around the pan. Many of the rocks on Kubu are white, and covered in old fossilized guano from the water-birds that used to come here when it was a lake.
On the southern part of Kubu island are located a dry stone wall, 1.25 meter high, in a form of letter "C". Outside of the circle are a number of stone cairns. The shoreline is littered with Stone-Age tools, arrowheads and glass beads. Archaeologists believe these walls belonged to the dynasty of Great Zimbabwe in the time period between 1400 and 1700 AD. This place could have been a remote 'circumcision camps' to which the boys of the tribe were taken for circumcision and the ceremonies leading to adulthood.
The people of the nearest village hold Kubu Island and the nearby Thithaba Islands as sacred, and men over 16 years of age visit the islands to make contact with God, singing a particular song for rain and leaving offerings on the ground.
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