The Darvaza Gas Crater, also known as the "Door to Hell," is a large, burning sinkhole located in Turkmenistan's Karakum Desert. It was created in 1971 when Soviet geologists were drilling in the area and accidentally punctured a large underground natural gas deposit. The ground beneath the drilling rig collapsed, and the gas began to burn uncontrollably. To prevent the spread of the toxic gases, the geologists set the crater on fire in an attempt to burn off the gas. However, the fire has been burning continuously for over four decades, creating a large and spectacular natural phenomenon that has become a popular tourist destination.

The Darvaza Gas Crater is approximately 70 meters (230 feet) wide and 30 meters (98 feet) deep. The fire within the crater burns with a bright orange flame, illuminating the surrounding desert landscape at night. Visitors to the site can get close enough to feel the heat of the fire and admire the unique natural phenomenon. The gases produced by the fire are toxic, so it is not safe to linger too close for too long.