The Door to Hell, Turkmenistan
The Door to Hell is a fascinating place. Located deep in the bleak Karakum Desert, in remote Turkmenistan, just getting here is a considerable challenge. But those who do make the difficult pilgrimage find the experience rewarding.
The fire that lights the night skies here has been burning for more than four decades, but the blaze could soon be extinguished. Natural gases have long fuelled the dramatic Door to Hell, but the reserves are not limitless.
You can go right to the edge and see the crater that formed during a drilling accident in the 1970s. It is enormous, measuring 225 feet from one side to the other, and almost 100 feet deep. The fire began when the ground beneath a Soviet drilling rig gave way, starting an inferno that still rages. But the blaze cannot last forever and those keen to take a peek are advised to get on with it.