[1] When the atmospheric temperature of the region rises the essential oil produced from the eucalyptus species evaporates and disperses in the air, causing visible spectra of sunlight to scatter.

The property, which includes eight protected areas in two blocks separated by a transportation and urban development corridor, is made up of seven national parks as well as the famous Jenolan Caves Karst Conservation Reserve.

It is particularly noted for its wide and balanced representation of eucalypt habitats from wet and dry sclerophyll, mallee heathlands, as well as localized swamps, wetlands, and grassland.

Ninety-one species of eucalypts (13 percent of the global total) occur in the Greater Blue Mountains Area.

Thought to have been extinct for millions of years, the few surviving trees of this ancient species are known only from three small populations located in remote, inaccessible gorges within the area.

These include threatened or rare species of conservation significance, such as the tiger quoll, the koala, the yellow-bellied glider, and the long-nosed potoroo, as well as rare reptiles and amphibians including the green and golden bell frog and the Blue Mountain water skink.

[8] The area totals roughly 10,300 square kilometres (4,000 sq mi), including the Blue Mountains, Kanangra-Boyd, Wollemi, Gardens of Stone, Yengo, Nattai and Thirlmere Lakes National Parks, plus the Jenolan Caves Karst Conservation Reserve.