Derweze, Türkmenistan: The Gate to Hell
Darvaza inhabitants are mostly Turkmen of the Teke tribe, preserving a semi-nomadic lifestyle.
While drilling in 1971, Soviet geologists tapped into a cavern filled with natural gas. The ground beneath the drilling rig collapsed, leaving a large hole with a diameter of 70 metres.
To avoid poisonous gas discharge, it was decided to burn it off. Geologists had hoped the fire would use all the fuel in a matter of days, but the gas is still burning today.
In April 2010, the President of Turkmenistan Gurbanguly Berdimuhamedow visited the site and ordered that the hole should be closed, or other measures be taken to limit its influence on the development of other natural gas fields in the area.