How Were The Glass House Mountains Formed?

How Were The Glass House Mountains Formed?

The Glass House Mountains are a group of thirteen hills, that rise abruptly from the coastal plain on the Sunshine Coast. They are located near Beerburrum State Forest and Steve Irwin Way, the highest being Mount Beerwah at 556 metres above sea level. The Volcanic peaks of the Glass House Mountains rise dramatically from the surrounding Sunshine Coast landscape.

The Glasshouse Mountains were formed from volcanic activity about 26-27 million years ago. They were formed as molten rock was forced out of vents from within the earth. As these flows of magma cooled over a period they solidified into conal shapes of hard rocks. The cores of the hills contain columns of comendite from lava, which cools quickly into a hard rock.

At the time, this volcanic activity had pushed the ground level higher, but erosion of the surrounding softer sand stone over millions of years has lowered the ground level to where we live to day. The only testimony to this violent volcanic era are the spectacular volcanic plugs that remain today.

The peaks’ location relative to each other exhibits an alignment that is believed to have occurred due to fracturing.

Mount Beerwah at 556 metres high is the “Mother by legend” and the grandest of all the mountains. The next highest is Mount Tibrogargan, which is relatively smaller at 364 metres, but the most identifiable of all the hills because, from certain angles, it bears a resemblance to a face staring east towards the ocean.

A total of 13 mountains of various sizes cover an area of over 600,000 hectares from Mt Mellum in the north to Round Mountain south of Elimbah, to the lesser Wild Horse Mountain at 123 metres high on the Bruce Highway to the east.

One of the most accessible places to view the mountains from is lookout 589. Just a short drive off Old Gympie Road and from most of the local tourist attractions, the magnificent views are worth every kilometre.

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