Simon and Gaye Terry ply the tranquil waters downstream from the sinuous sandstone ravine of Cobbold Gorge Nature Refuge. 

The Archway Complex in Undara Volcanic National Park, home to the dormant Undara Volcano, its crater rim standing a paltry 20m above the surrounding plains. However, in vulcanism, elevation isn’t everything. Beginning 190,000 years ago, Undara erupted and created 160kms of tubes, tunnels and arches, in one of the world’s longest recent lava flows. 

Sunrise from the top of Cobbold Gorge. The gorge is but one feature in a vast sandstone ­stronghold found here in Far North Queensland, roughly 250km north-west of Townsville. The sandstone’s blocky surface of weathered fissures and mushroom-shaped outliers has echoes of its cousins in the Kimberley and Arnhem Land. Walking up on top is like navigating a maze. Along with that enigmatic character comes the tantalising promise of more hidden gorges waiting to be discovered.

Pockets of vine thicket sprout in moist depressions created by the collapse of sections of lava tube roofs. Where the lid remains intact, long stretches of hollow lava tube survive. 

At Barkers Cave the combined micro-bat population is 40,000-strong. 

Barkers is a maternity cave where bats congregate to nurse their young.

Tree snake scales glisten as many dangle head-first into the main flight path of the bats, ready to strike at an abundant flying dinner. 

Trezkinn Cave in Chillagoe-Mungana National Park is a limestone cave derived from coral reefs and sediments deposited in a succession of warm seas about 400 million years ago.

A view of Cobbold Gorge from above.

While there was knowledge of the ravines that slice into this craggy barrier, few had been explored since European settlement. That changed in 1992 when local Simon Terry got together with a couple of old schoolmates. Equipped with a tinny and an outboard, they headed upstream from a waterhole at the end of Cobbold Creek, a tributary of the Robertson River. To their astonishment they soon entered a dramatic sheer-sided chasm that kept wriggling its way deep into the sandstone country.

Sunset overlooking Undara Volcanic National Park. There’s much more to this canvas than termite mounds and lava tubes. For all its green-season garb, the brawny frame of the landscape is unmistakeable.

The powerhouse chimney stands in front of the main smelter chimney on the hill in Chillagoe township. These ties to geology go way back. Copper mining played a pivotal role in opening up the Gulf Savannah from the late 19th century and the rail line to Forsayth was part of an ambitious network created to support smelters at Chillagoe. 

A snaking river makes its way through the woodland and savanna grassland surrounding the Gulf of Carpentaria.

In 2009 the Terry family established the 4720ha Cobbold Gorge Nature Refuge, which protects a number of vulnerable and rare plant species and also forms important wildlife corridors and catchment linkages. Visitors can come and stay, and there are a number of tours run by the family. 

Chillagoe-Mundana National Park ranger Eddie Thomas at Castle Rock, an Aboriginal rock art site near the park.

The enterance to Donna Cave, Chillagoe-Mundana National Park. This section of the cave has been dubbed ‘Madonna’ for the shadow the formations cast on the interior wall.

More than 60 relic caves have been explored. They’re geological powerhouses, daubed in colourful mineral oxides and etched with the scars of their fiery birth.

Inside the Archway Complex lava tube. 

A bat hanging inside Trezkinn Cave in Chillagoe-Mundana National Park.

Trezkinn Cave in Chillagoe-Mundana National Park is a limestone cave derived from coral reefs and sediments deposited by a succession of warm seas about 400 million years ago.

As gorges go, Cobbold is a pup. For most of its life this creek joined the Robertson River via a wide watercourse some 15km upstream. However, at some point – and perhaps as recently as within the last 10,000 years – the flow was diverted into a slender gully heading north-east to the Robertson. Although the mechanism for this change of direction is open to debate, the end results are startling.