The Aral Sea in Central Asia was once the world's fourth biggest inland sea, and one of the world's most fertile regions. But economic mismanagement has turned the area into a toxic desert.
The two rivers feeding the sea, the Amu Darya and the Syr Darya, were diverted in a Soviet scheme to grow cotton. Between 1962 and 1994, the level of the Aral Sea fell by 16 metres.
The surrounding region now has one of the highest infant mortality rates in the world, and anaemia and cancers caused by chemicals blowing off the dried sea bed are common.