Apocalyptic

You awaken in a bunker, deep beneath the Rocky Mountains. You do not remember how you got here, but a wall map gives you a clue of your surroundings. You are on the 3rd level beneath the earth, with 7 more to go, and what seems to be a massive airlock level for the entrance. The bunker seems to be devoid of life, but there are signs of recent activity around. Everything is dusty and old.