The Door To Hell (Credit: Huffington Post) at Turkmenistan.
The Door To Hell is located on top of the natural gas field in Turkmenistan. Soviet geologists found and drilled for natural gas here in 1971 when the ground began to collapse to leave a large crater. To prevent inhalation of poisonous gas, the crater was set on fire, believing the natural gas would quickly be burned off and the fire would go out. However, the fire pit is still burning today with no signs of letting up from the seeping natural gas. There have been many failed attempts to put the fire out.