Why are Blue Mountains blue?

What has made this bushland mountain region look one pure blue colour from afar?

Nestled only a couple hours away from the bustling city of Sydney, The Blue Mountains is perfect for a day away where travellers can step into a valley of mesmerizing mountains dense with Australian bushland and natural wonders. The region is one of the dreamiest destinations in all of New South Wales, home to unique wildlife and breathtaking views. But many people are confused by the name of the region, so where does the name Blue Mountains exactly come from?

The Blue Mountains Formation

Back million years ago, the sea completely covered the area. While the sea level was so high, bucket loads of residue dropped into the water, covering the floor and eventually compressing into sandstone and shale. Eventually, the water lowered, leaving behind hard rocks, and due to the continuous erosion by the water and weather, the rock slowly moulded into hills. Even further moulding came about after continuous volcanic eruptions caused lava to flow through the cracks of rock. All this took about 250 million years, the area naturally formed spectacular mountains, rock formations, deep canyons, cascading waterfalls, and lush forestland covering the area.

The Blue Mountains History

Due to its size, there is a rich history in each section of Mountain. With six separate Aboriginal tribes who hold connections with this land. They include Darug, Gundungurra, Dharawal, Darkinjung, Wanaruah and Wiradjuri. European settlers did not venture into the area until 1813 as the land was thick in the impermeable forest. However, soon parts with cut down to make room for open plains for farming and settlement.

The Reason behind the Blue

You may be confused about the name due to the mountains look a lot greener than blue, with their lush bushlands carpeting the mountains and gorges. But in fact, the name is actually completely due to the type of bushland inhabiting the mountains, more specifically, the eucalyptus tree! The eucalyptus’ are spread throughout mountain tops, and is one of the most common plant types found around. Also named gum trees, these trees are a significant species in the Blue Mountains, being the only food source for the beloved koalas, as well as being a home to the native birds. One of the main factors of the eucalyptus tree is the oil found in the leaves, which are used for a number of benefits for humans. However, the scorching sun of Sydney plays a factors to these trees, slowly heating up the leaves until the oil seeps out in a mist. This oil fume mist covered the area, creating a beautiful crisp bush smell within the region. Although the mist cannot be seen up close within the mountaintops, the mist can be seen reflected by the light at a distance, making the region looking like it is engulfed in a blue haze. When looking at the mountains from Sydney in particular, the oil fog covers the entire range, resulting in the mountains to look blue from afar.

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