What Is the Oldest Fire Still Burning on Earth?

The oldest fire still burning on Earth is an underground coal seam fire beneath Burning Mountain in Australia that has been continuously burning for approximately 6,000 years. This ancient fire began from a lightning strike and has never been extinguished, predating the construction of the Egyptian pyramids.

The Ancient Fire Beneath Burning Mountain

Located in New South Wales, Australia, Burning Mountain (Mount Wingen) sits atop one of the most remarkable geological phenomena on our planet. The coal seam fire burning deep underground generates temperatures so intense that the surface ground becomes too hot for vegetation to survive. This natural sterilization process creates a barren landscape above the fire’s path, marking its slow but steady progression through the mountain.

Early European explorers who encountered this mysterious mountain initially mistook it for an active volcano. The heat, smoke, and barren ground seemed to indicate volcanic activity, but they were actually witnessing something far more ancient and unusual—a fire that had been burning since before recorded human civilization in the region.

How Underground Coal Fires Work

Coal seam fires occur when underground coal deposits ignite and continue burning due to the available oxygen in the surrounding rock and soil. Once started, these fires can be nearly impossible to extinguish because they burn deep underground, making them inaccessible to traditional firefighting methods. The fire slowly moves through the coal seam, consuming the fossil fuel and releasing heat, smoke, and gases.

The Burning Mountain fire moves at an incredibly slow pace—approximately one meter per year toward the south. At this rate, scientists estimate the fire could continue burning for thousands more years, as long as coal deposits remain in its path and oxygen continues to feed the flames.

A Global Phenomenon

Burning Mountain is not unique. Underground coal fires burn on every continent except Antarctica, representing a largely hidden environmental challenge. Some of these fires release more carbon dioxide into the atmosphere than entire countries produce through industrial activities. China alone has hundreds of underground coal fires, and similar fires burn in the United States, India, Indonesia, and other coal-rich regions.

These fires often start from human activities such as mining operations, but natural causes like lightning strikes, spontaneous combustion, or forest fires can also ignite underground coal seams. Once established, they can burn for decades or even centuries, slowly consuming vast underground coal reserves.

Environmental and Scientific Impact

The environmental implications of these underground fires are significant. They release substantial amounts of carbon dioxide, carbon monoxide, and other greenhouse gases, contributing to climate change in ways that scientists are only beginning to understand. The continuous burning also represents a loss of valuable coal resources and can make land above unusable.

For scientists, these fires provide unique opportunities to study long-term combustion processes and their effects on local ecosystems. The Burning Mountain fire, in particular, offers insights into how underground fires behave over millennia and their impact on surface geology and biology.

The Hidden Reality

The existence of these ancient, ongoing fires highlights how much about our planet remains unknown or underappreciated. While humans focus on visible environmental challenges, the Earth has been quietly burning beneath our feet for thousands of years. These underground infernos represent a fascinating intersection of geology, climate science, and environmental studies that continues to reveal new insights about our planet’s complex systems.