Ancient craters and underground lava tunnels tell the tale of a violent volcanic past


It’s pitch black. We’re standing in a giant underground tunnel created hundreds of thousands of years ago by a volcano. “Turn your torches on again,” says our guide. The light brings to life the surprising colours of our surrounds, with white, brown and orange decorating the surface of the lava tunnel. This feels like a journey to the centre of the earth!

Undara Volcanic National Park is around 300km southwest of Cairns, to the west of the McBride Plateau, on the eastern end of Tropical North Queensland’s Gulf Savannah region. The name ‘Undara’ came from the Aboriginal word meaning ‘long way’. The traditional custodians of this region are the Ewamian Aboriginal people.


The landscape here has been shaped by an explosive volcanic history over the past 8 million years, during which an incredible 150 volcanic vents were active. This includes Undara, lying at the centre of the McBride Volcanic Province.

Around 190,000 years ago, the land trembled, the sky glowed orange and scarlet, and red hot molten lava poured out of the Undara volcano to engulf 1550 square kilometres of land. As the lava spread across the landscape, it flowed down riverbeds and creeks. Exposed to air, the top layer cooled rapidly and solidified, creating a hard outer shell. This insulated the molten lava beneath which continued to flow, leaving behind enormous empty tubes around 20 metres wide and 10 metres high.

Assisting the lava flow was the unusually hot magma, exceeding temperatures of 1200 degrees Celsius, which served to make it more fluid. Also aiding the steady flow of lava was the sloping land to the west of the Great Dividing Range and the dry, sandy soil.

The lava flowed 160km northwest, the longest recorded distance in the world, and over 90km to the north.

It seems incredible that Undara erupted for the last time less than 20,000 years ago.

Over the years, weaker sections of the roofs have collapsed, providing access to the tunnels and creating depressions and numerous large caves.

The park now protects these lava tube cave systems, the finest in Australia. They contain unique ecosystems of international significance. Rare, ancient vine-thicket rainforest related to Gondwana species from around 300 million years ago flourish in the moist collapsed depressions of the lava tubes. Wildlife, such as rock-wallabies, bats, reptiles and owls shelter in the cool caves. In order to protect the delicate ecosystems and to keep visitors safe, access to the lava tunnels is by guided tour only.


A great way to begin your exploration of Undara is the 2.5 kilometre Kalkani Crater Rim Walk – this moderate walk is accessible without a guide and will take you about an hour and a half. It’s an easy 16km drive from nearby Undara Experience resort, part of it along a gravel road. The track begins by rising gradually up to top of the 50m-high crater and then skirts around the rim. Once at the top, it will become obvious that you are walking around the circular rim of a volcano. The centre of the crater is somewhat sunken and is filled with vegetation.

From atop the crater you’ll have impressive views over the national park, with unmistakable extinct volcanoes scattered around, rising sharply from the flat lava plains. If you look closely, you’ll see the course of the lava tubes marked by emerald-green rainforest. These ribbons of green provide a stark contrast to the dry savannah woodland.

There are interpretive signs to enhance your understanding of the walk, as well as seats providing places to rest and take in the spectacular vistas. Along the way, you’re quite likely to meet some local residents – we were fortunate enough to spot an agile wallaby, a snake and a dingo running through the grassy savannah.

We booked a lava tube tour through Undara Experience resort and looked forward to our geological journey back in time. Our guide took us firstly to a rocky lookout with a fabulous view of Kalkani Crater and the misty clouds over the Atherton Tablelands. On a clear day, you can also see Undara Crater.

Our next stop was the Wind Tunnel Complex. As we neared the entrance, we walked past striking Queensland Bottle Trees, looking like a slimmer version of boab trees. Some had foot markings made by Aborigines climbing the trees. Then we moved on into our first giant lava tube; the two open ends clearly visible. This is a gentle first experience of the volcanic underground world. Interesting patterns can be seen on the walls and roofs made by cracks which formed as the lava cooled and minerals that have been deposited from water seeping through from the surface.

Journeying further underground, we entered a large multi-forked tube. We could see the various levels of lava flows etched into the walls like tidal marks, and a raised, rounded section of the roof at the first fork junction, apparently pushed up by increased heat from the lava as it pooled at the junction. Total darkness enveloped us as we made our way into the centre of a long tube.

At another site we explored the blind ended tunnel known as Road Cave, with its small spring and baby ferns at the entrance. The tunnels can flood during extreme wet conditions. Small bats live on the ceiling and in crevices.

There is also a two-hour, easy “Wildlife at Sunset” tour, which begins with sunset drinks and nibblies on a rocky knoll before visiting the entrance of Barker’s Cave. Here insect-eating micro-bats emerge from the darkness in their thousands as they search for food. You may see a brown tree snake or a python lying coiled at the entrance, waiting for a chance to snatch a meal as the tiny bats fly out.

Attesting to the geothermal activity continuing in the region, Innot Hot Springs makes an interesting side trip, 115km northeast along the Kennedy Highway. If travelling from Cairns, you can stop in on your way to Undara. The sandy Nettle Creek is literally steaming hot, with its thermal waters reaching 78 degrees Celsius! In places we found it too hot to stand. Faults in the rocks extend many kilometres below the springs. Water travels down the faults to a magma chamber where it is heated and forced back to the surface. Until the early 20th century, its ‘healing waters’ were bottled and exported to Europe.


The first white settlers in the area were the Collins family, who arrived in 1862. Born in England, Thomas and Charles Collins claimed 100 square miles of land around 40km to the south of Undara after one of their bullocks strayed and found a spring-fed creek. They called the pastoral property Spring Creek Station, in honour of this important source of water.

The neighbouring Rosella Plains Station, named after the native rosella plants, was purchased by Thomas Collins in 1901, for his younger son Bram to manage. His elder son, Victor, continued to manage Spring Creek Station. After five generations in the Collins family, the Queensland Government bought Rosella Plains in 1992 and incorporated it into Undara Volcanic National Park.

Six generations later in the 1990s, the Collins family opened the Undara Experience to the public. Known as “Australia’s Accessible Outback”, the multi-award-winning Undara Experience is right next to the National Park. The Collins family say their aim is to preserve a unique treasure for future generations, and they’re keen for you to share their Undara Experience.

We enjoyed morning tea at Heritage Hut, a replica pioneer cottage similar to the one built by the Collins brothers as their first home on Spring Creek Station. It sits on the banks of the pretty Iron Pot Creek, and can be reached via the 3.6km Pioneer Track bush walk, an easy walk of between two and three hours, accessed from the resort. The track follows the route of the historic 1870s telegraph line and passes historical attractions with interpretive signage along the way.

‘Undara Central’ is the hub of the resort with dining facilities, a bar and campfires. Superbly restored train carriages from the early 1900s form the dining and saloon bar area and also provide accommodation along an original Cobb and Co coach road in the resort.

We enjoyed dining in one of the old rail carriages at the licensed Fettlers Iron Pot Bistro. If you like good ol’ country cooking, you’re in the right place – and you simply must try the Undara Chocolate Volcano! The Saloon Bar is a great spot for a game of pool and a drink in a lovely covered outdoor setting.

The bush campground provides spacious, shady sites with individual campfires, and you should expect a kangaroo to drop in for a visit! There’s also an enticing billabong-style swimming pool where you can cool off or relax on the deck chairs. A small selection of groceries, ice and guest supplies are available.

Visiting Undara is certainly an experience. Emerging from the dark confines of an ancient lava tube into the bright sunshine is like stepping forward in time, from the raw geological forces that have built our amazing county back to the present day. Geological time travelling sure is a blast!