Australia is the smallest continent and the biggest island in the world. It is situated between the Pacific and the Indian Oceans. There are two great deserts in Australia: the Great Sandy Desert and the Great Victoria Desert. There can be also found 335 meters high Ayers Rock, the largest piece of rock in the world. Australia has two big rivers, the Murray and the Darling, and three great lakes: Lake Eyre, Lake Torrens, and Lake Gairdner. The highest mountalin is Mount Kosciusko (2,228 m) discovered by Paul Edmund de Strzelecki and Thaddeus Kosciusko in 1840. Australia has many different kinds of climate: tropical in the north, continental in the interior, sub-tropical or temperate in the rest of the continent. South-eastern Australia, including Tasmania, has the highest incidence of bushfires in the world. In 1994 bushfires swept through New South Wales, destroying hundreds of homes in suburban Sydney.