The Nightcap Range is the wreckage of fire. It forms the southern flank of an enormous shield volcano, centred on the peak the Bundjalung call Wollumbin, that erupted more than 23 million years ago and has been eroding ever since into gullies, ridges and a massif of green-cloaked peaks. The tallest, Mount Burrell, also known as Blue Knob, reaches 933 metres. Old basalt and rhyolite lava have weathered into different soils, and the forest answers in kind: warm temperate rainforest on the rhyolite, lush subtropical rainforest on the richer basalt ground. This is the wettest country in the state, soaking up more than 2,500 millimetres of rain a year, and the forest drinks every drop.

By the late 1970s, the logic of the chainsaw still ruled the public forests, and the rainforest of Terania Basin was scheduled to fall. What happened instead changed the country. Around a hundred people formed a human barricade against the machines, holding the line through a long and tense standoff. "So overpowering was the draw of these trees that people risked their lives," the Green politician Ian Cohen later recalled. "A spirit of transformation emanated from the forest." The protest forced the New South Wales government to end rainforest logging across the state. Nightcap was declared a national park on 22 April 1983, and three years later the wider Gondwana Rainforests earned World Heritage listing. The waterfall at the heart of the battle is now, fittingly, called Protesters Falls.

What the blockade preserved is genuinely irreplaceable. The park shelters survivors of the Big Scrub, once the largest area of subtropical lowland rainforest in Australia, now reduced by clearing to less than one percent of its former extent. These lineages descend from the forests of the ancient supercontinent Gondwana, which is why the World Heritage area bears its name. The park's rarest tree, the Nightcap oak, was unknown to science until 2000 and grows wild as a single population on the southern side of the range; fossil relatives of its kind have been found dating back 15 to 20 million years, hinting at a time when such forests were widespread. In the wet undergrowth live creatures found almost nowhere else, from Albert's lyrebird and the jewel-bright regent bowerbird to the spotted-tailed quoll and a clutch of endangered frogs whose survival depends on these clean, cold streams.

Rainforest is not built to burn, which made the summer of 2019 to 2020 a terror. The catastrophic bushfires of that season swept into a park that had rarely known flame, and conservationists feared the worst for the ancient Nightcap oaks. The aftermath held a fragile hope: most of the scorched trees regenerated, with fewer than a fifth dying, and ground-dwellers like the red-legged pademelon and long-nosed potoroo came through largely unharmed, though others, such as the golden-tipped bat, likely suffered. The forest that people once defended with their bodies now faces a slower, harder threat in a warming climate, and its survival, once again, is not guaranteed. The lesson of Terania Creek was that this place is worth fighting for. That lesson has not expired.