They are one of the most stunning mountain ranges in New South Wales, but how did the Blue Mountains get their name?

Formed over 2 million years ago, the Blue Mountains were initially named “Carmarthen Hills” and “Landsdowne Hills” by Governor Arthur Phillip in 1788. However, these names didn’t last long, and the range was promptly renamed the Blue Mountains. When viewing the mountain range from afar people noticed the mountains have a distinct blue haze over their peaks.

How are they blue?

The Blue Mountains are famously rich in eucalyptus trees and it is these that create a blue haze which gave the mountains their name. Across Australia, there are four types of eucalyptus trees and the top of the Blue Mountains feature them all.

Many people know eucalyptus for its distinctive scent. This comes from the tree’s leaves which are covered in oil glands and it is the oil that is scented. Humans use eucalyptus oil for a variety of tasks; from clearing colds and mopping floors to controlling allergies and reducing muscle pain. The trees, however, use the oils to protect themselves from pests that may want to eat their leaves. Interestingly, it is this oil secretion that changes the colour of the mountains!

With such a dense population of eucalyptus trees secreting oil, there is a high concentration of oil in the air and this causes the blue haze. As the tiny droplets combine with dust particles and water vapour, the light passing through it is refracted, and when it reaches the human eye, it appears blue!

Essentially, the particles create a blue light filter across the horizon – it’s like Instagram in real life!

Viewing the haze

The blue haze over the mountain range can be seen throughout the day. As the colour is caused by the presence of oil in the air, rather than fog, it hovers across the horizon from dawn to dusk. To best see this phenomenon, head to one of the many lookouts scattered throughout the ranges and look across the trees and into the distance.

Take a walk to the ranges most popular lookout, Echo Point. Here you will have stunning views of the eucalyptus forests that cause the blue air, plus you’ll find yourself in the perfect place to see the famous Three Sisters rock formation.

Don’t feel like walking there? No worries! Head down to Scenic World and board their skyway or cableway. Ride through the sky between the cliff faces with 360° views of the Blue Mountains. Stand on the electro-glass floor to see the forests below you and soak in the beauty of the mountain range.

The Blue Mountains and their abundance of blue haze causing eucalyptus trees became World Heritage Listed in 2000, in acknowledgement of this natural sensation.

Though pictures of the Blue Mountains are stunning, nothing beats standing there yourself, so start planning your trip today!