<Tr> <Th> Age of rock </Th> <Td> Tertiary </Td> </Tr> <P> The Glass House Mountains are a group of thirteen hills that rise abruptly from the coastal plain on the Sunshine Coast, Queensland, Australia . The highest hill is Mount Beerwah at 556 meters above sea level, but the most identifiable of all the hills is Mount Tibrogargan which from some directions appears to be a face staring out to sea . Mt Ngungun consists of sub-volcanic rock, also known as a hypabyssal rock, an intrusive rock emplaced at medium - to - shallow depths within the crust and has intermediate grain size, and often porphyritic texture between that of volcanic and plutonic rocks . Mount Ngungun and the Glass House Mountains are located near Beerburrum State Forest and Old Gympie Road . From Brisbane, follow the Bruce Highway north, take the Glass House Mountains tourist drive turn - off and follow the signs to the Glass House Mountains . The trip is about one hour and eleven minutes from Brisbane . The Volcanic peaks of the Glass House Mountains rise dramatically from the surrounding Sunshine Coast landscape . They were formed by intrusive plugs, remnants of volcanic activity that occurred 26 - 27 million years ago . Molten rock filled small vents or intruded as bodies beneath the surface and solidified into land rocks . Millions of years of erosion have removed the surrounding exteriors of volcanic cores and softer sandstone rock . </P> <P> Whilst the traditional names for the hills themselves are very old, the term' Glasshouse Mountains' was given more recently by explorer Captain James Cook on 17 May 1770 . The peaks reminded him of the glass furnaces in his home county of Yorkshire . Matthew Flinders explored the area and climbed Mount Beerburrum after sailing along Pumicestone Passage in 1799 . The Glass House Mountains National Landscape was added to the Australian National Heritage List on 3 August 2006 . In the land between the peaks, pineapple and poultry farming, as well as commercial forestry and quarrying are the main land uses . </P> <P> In 2009 as part of the Q150 celebrations, the Glass House Mountains was announced as one of the Q150 Icons of Queensland for its role as a "Natural attraction". </P>

Where did the glass house mountains get their name
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