Black Mountain (Kalkajaka, 'place of spears') is a 1,640-foot pile of enormous black granite boulders roughly 25 kilometres south of Cooktown on the far north Queensland coast. Sacred to the Kuku Nyungkal, Eastern Kuku Yalanji, and neighbouring Aboriginal peoples — who identify it as the home of ancestral beings and warn visitors emphatically not to enter the talus — the mountain has been linked to more than a dozen documented disappearances since European contact in the late 1800s. The surface of the mountain is a labyrinth of house-sized boulders with bottomless cavities and unventilated tubes; surface temperatures can exceed 60°C and the interior emits a low hum that has been variously attributed to wind, bat populations, or unknown source.
Among the recorded disappearances: in 1877, two European gold prospectors named George Hawkins and Renn vanished while camping at the mountain's base and were never found. In 1890, a stockman named Owens disappeared pursuing cattle onto the talus slopes; search parties found his horse but no trace of the man. In 1908, an Aboriginal stockman named Jack Clegg entered a crevice looking for his dog and did not re-emerge despite three days of searching. In 1932, Constable Rylatt of the Cooktown Police disappeared near the summit while investigating cattle theft. In 1962, a team of five experienced cavers entered a major boulder cavity with ropes and lighting; only three returned, and none would ever discuss what they saw. Most recently, a German backpacker named Schwarz went missing in 1988.
The Queensland Department of Environment and Science has gazetted Black Mountain as a no-access site for traditional-cultural reasons, enforcing substantial fines for entry. Low-frequency infrasound measurements by JCU researchers in the 1990s detected unusual acoustic resonance from the rock pile. Whether the site represents an Aboriginal sacred space whose geological features produce disorienting conditions, or something more inexplicable, Black Mountain is one of the most concentrated clusters of unexplained-disappearance reports in Australia.