Possible Clues:

• Antarctica volcano
• Greek personification of darkness
• Sure it's about ot be back down below
• Before you get transport to get you down
• Darkness to be traversed, before getting public transport?
• Sure, be in the underworld
• You may get down to it before there's transport
• Dark and gloomy cavern between earth and Hades.
• Is there e'er the sound of a car down there?
• Mt. -, Antarctic volcano; be sure (anag.)