Mount Nardi belongs to the Nightcap Range, a spur of the Great Dividing Range that forms the southern rim of the Mount Warning, or Tweed, shield volcano. The range was raised over 23 million years ago by successive lava flows, and the rock beneath the rainforest still records that violence in three distinct layers: Lismore Basalt, Nimbin Rhyolite, and Blue Knob Basalt. Each represents a different pulse of the volcano, a different temperature and chemistry of molten rock. The mountain you climb today is the cooled, eroded leftover of an eruption that reshaped the entire region.

The Bundjalung nation has long held this country, and the people who spoke the Widjabal language crossed the range by foot-tracks, keeping small grassed clearings in the forest for camping and hunting. European loggers came in 1842, drawn by red cedar - the prized "red gold" of the colonial timber trade. The lowlands below were once the Big Scrub, one of the largest stretches of lowland subtropical rainforest in eastern Australia, nearly 75,000 hectares of it. By 1900, after decades of clearing for dairy farms, less than one percent remained. The historic Nightcap Track that crosses the peak began as a path worn by postal workers carrying mail between Lismore and Murwillumbah.

In 1962 the first tower went up on the summit - RTN-8, now NRN-8 - to carry analogue television, and a bitumen road, Newton Drive, was cut up from Nimbin to reach it. More masts followed: the ABRN-6 tower in 1964, raised by the ABC and later switched from the Brisbane network to Sydney, and a Telstra tower in 1975, since demolished and rebuilt. Today the three structures push digital television, ABC and community radio, NBN wireless internet, and 4G and 5G mobile signal out across the Tweed, the Gold Coast, Lismore, and Byron Bay. The carriers share the ridge like neighbours: Telstra on its own mast, Vodafone borrowing space on the ABRN-6 tower, and the whole site run by a single operator. When analogue TV switched off in 2012, the original tower found new life broadcasting the community station Triple Z FM. It is an oddly fitting summit for the region - the same high ground that once carried mail on foot now carries the signals that bind the whole north coast together.

For all its steel, Mount Nardi remains a place of quiet. A small picnic area near the summit offers shaded tables and shelters, toilets and information signs, and long views across Nightcap National Park and the neighbouring Whian Whian State Conservation Area - the surviving rainforest that the Terania Creek protesters fought to save in 1979, and that UNESCO recognised as World Heritage in 1986. Walking trails fan out from the top, including the Mount Matheson Loop and Pholi's Walk, both part of the historic Nightcap Track. This is fragile country: the same World Heritage forests have been scarred by bushfire in recent years, a reminder that even an ancient rainforest is not guaranteed against a warming climate. Stand among the antennas, turn your back on them, and you face one of the oldest forest lineages on the continent.