of three of the members of the transcontinental party. The Overland Telegraph line was constructed in the 1870s along the route identified by Stuart. In 1865, the surveyor George Goyder, using changes in vegetation patterns, mapped a line in South Australia, north of which he considered rainfall to be too unreliable to support agriculture. Exploration of the Outback continued in the 1950s when Len Beadell explored, surveyed and built many roads in support of the nuclear weapons tests at Emu Field and Maralinga and rocket testing on the Woomera Prohibited Area. Mineral exploration continues as new mineral deposits are identified and developed. 2002 was declared the Year of the Outback. While the early explorers used horses to cross the Outback, the first woman to make the journey riding a horse was Anna Hingley, who rode from Broome to Cairns in 2006. Environment Global significance The paucity of industrial land use has led to the Outback being recognised globally as one of the largest remaining intact natural areas on Earth. Global "Human Footprint" and wilderness reviews highlight the importance of Outback Australia as one of the world's large natural areas, along with the Boreal forests and Tundra regions in North America, the Sahara and Gobi deserts and the tropical forests of the Amazon and Congo Basins. The savanna (or grassy woodlands) of northern Australia are the largest, intact savanna regions in the world. In the south, the Great Western Woodlands, which occupy , an area larger than all of England and Wales, are the largest remaining temperate woodland left on Earth. Major ecosystems Reflecting the wide climatic and geological variation, the Outback contains a wealth of distinctive and ecologically rich ecosystems. Major land types include: the Kimberley and Pilbara regions in northern Western Australia, sub-tropical savanna landscape of the Top End, ephemeral water courses of the Channel Country in western Queensland, the ten deserts in central and western Australia, the Inland Ranges, such as the MacDonnell Ranges, which provide topographic variation across the flat plains, the flat Nullarbor Plain north of the Great Australian Bight, and the Great Western Woodlands in southern Western Australia. Wildlife The Outback is full of very important well-adapted wildlife, although much of it may not be immediately visible to the casual observer. Many animals, such as red kangaroos and dingoes, hide in bushes to rest and keep cool during the heat of the day. Birdlife is