No, I don’t have the answer for the actual door to hell. This is the nickname given to the “Darvaza Crater” in Turkmenistan. The crater is a actually a natural gas fire burning continuously for last 40 years, most possibly the result of a drilling mishap.
George Kourounis, a Canadian explorer, became the first person who dared to face the heat and set foot on the bottom of the hell. The mission was to gauge if life can exist in these extreme conditions. Read the news here.
Read the interview on National Geographic