What's special?:
This park contains the remains of the Earth’s longest flow of lava originating from a single volcano. Caves within this lava tube are fertile pockets in which rainforest plant and animal species thrive.

Park Features:
On the western slopes of the McBride Plateau, open woodlands give way to the vast open spaces of the savanna. Here in Undara Volcanic National Park, rich volcanic basalt soils, covered in a sea of seasonal grasses, conceal the Undara lava tube. This geological tunnel of global significance snakes westward under a ribbon of remnant deciduous rainforest.

“Undara” is an Aboriginal word meaning “long way”. The park protects one of the longest lava tube cave systems in the world. About 190,000 years ago a large volcano erupted violently, spewing molten lava over the surrounding landscape. The lava flowed rapidly down a dry riverbed. The top, outer layer cooled and formed a crust, while the molten lava below drained outwards, leaving behind a series of hollow tubes.

Semi-evergreen vine thicket grows in the moist, sheltered entrances to some of the lava caves. The roofs of some tubes collapsed, creating ideal conditions for dry rainforest to grow and wildlife to shelter. Rock-wallabies, insectivorous bat colonies and owls roost here in the cool. Birds shelter in the fruit-filled canopy and predators lurk in the tumbled basalt terrain to complete the food chain. The collapsed tubes have also created mysterious caves for us to explore.

Natural Environment:
Landscape and Geology:
For millions of years Undara was an active shield volcano. About 190,000 years ago, in the Cainozoic era, there was a massive eruption and lava flowed more than 90km to the north and over 160km to the north-west. An estimated 23.3 cubic kilometres of lava flowed from the volcano at a rate of about 1000 cubic metres every second. A lava flow this large could fill Sydney Harbour in six days. It is thought that the lava flowed at a temperature of around 1200 degrees Celcius.

The lava tubes and caves were formed when rivers of lava confined to a valley crusted over and formed a roof. Insulated in its casing of solidified lava, the lava flow carried on for many tens of kilometres before draining out, leaving an empty tube of lava. Weaker sections of the roof of the tubes later collapsed to form caves and depressions. More than 50 caves have been found in the park.

The Undara lava tube system is Australia’s longest, and one of the longest in the world. It is also unusual if not unique in that it developed on a granitic basement. The lava tube caves in this national park are the finest examples in Australia and contain specialised ecosystems that are internationally significant. Bayliss Cave is considered one of the world’s most important, biologically diverse caves. Other examples of well-preserved volcanic features in the park include craters, lava ponds and flows, and perennial springs..