the globe says
Turkmenistan
The hard part: Turkmenistan issues visas mainly for guided tours or 5-day transit visas, and refusals are random. Fly to Ashgabat, then three hours into the Karakum.
A tent or yurt at the crater rim — there is nothing else, which is correct.
The Gates of Hell: a collapsed Soviet gas rig that has burned continuously since 1971, a hundred-meter fire pit roaring in absolute desert dark — plus Ashgabat, the white-marble capital of pure surrealism.
Arrive before dusk and watch the crater take over the sky as night falls. Stand upwind.
April to May, September to October
Sag boluň — thank you, in Turkmen.
Sacred Horses by Jonathan Maslow — Turkmenistan through its Akhal-Teke horses.
Konye-Urgench near the Uzbek border — shattered minarets of a city Genghis Khan erased.
The visa is a lottery and independent travel is essentially prohibited — apply months out through an agency and have a backup plan. The government periodically discusses extinguishing the crater; go before bureaucracy beats geology.