The oldest burning coal fire is six thousand years old!

Mount Wingen, known also by its more fitting name, Burning Mountain, is a hill in Australia. It is located in Wingen, New South Wales. The reason it is called Burning Mountain is the presence of a burning coal seam beneath the ground. The coal is believed to have been burning for more than 6,000 years in the sandstone. 

The hill is part of Burning Mountain Nature Reserve, which is worked by NSW National Parks and Wildlife Service. Visitors to the park can follow a trail along the hills from the parking lot. Along the trail they can read little signs about the area and also see the steam rising up from the oldest burning coal fire in the world! 

Originally, visitors to the area thought the smoke came from some sort of volcanic action. Since then, it has been discovered that the smoke has nothing to do with a volcano and just because of burning coal. The underground fire isn’t stationary, rather it is moving towards the south at a rate of one meter per year.

It may seem like a small distance, but over the time it adds up to a considerable distance.

(Source)