<P> Examples of Aboriginal habitation can be found in many places . In the Red Hands Cave, a rock shelter near Glenbrook, the walls contain hand stencils from adults and children . On the southern side of Queen Elizabeth Drive, at Wentworth Falls, a rocky knoll has a large number of grinding grooves created by rubbing stone implements on the rock to shape and sharpen them . There are also carved images of animal tracks and an occupation cave . The site is known as Kings Tableland Aboriginal Site and dates back 22,000 years . </P> <P> Arthur Phillip, the first governor of New South Wales, first glimpsed the extent of the Blue Mountains from a ridge at the site of today's Oakhill College, Castle Hill . He named them the Carmarthen Hills, "some forty to sixty miles distant ..." and he reckoned that the ground was "most suitable for government stock". This is the location where Gidley King in 1799 established a prison town for political prisoners from Ireland and Scotland . </P> <P> The first documented use of the name Blue Mountains appears in Captain John Hunter's account of Phillip's 1789 expedition up the Hawkesbury River . Describing the events of about 5 July, Hunter wrote: "We frequently, in some of the reaches which we passed through this day, saw very near us the hills, which we suppose as seen from Port Jackson, and called by the governor the Blue Mountains ." During the nineteenth century the name was commonly applied to the portion of the Great Dividing Range from about Goulburn in the south to the Hunter Valley in the north, but in time it came to be associated with a more limited area . </P> <P> The native Aborigines knew two routes across the mountains: Bilpin Ridge, which is now the location of Bells Line of Road between Richmond and Bell, and the Coxs River, a tributary of the Nepean River . It could be followed upstream to the open plains of the Kanimbla Valley, the type of country that farmers prize . </P>

Why is the blue mountains called the blue mountains
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