Hverfjall

From The Colonel's Website

Hverfjall is a large volcanic crater in close proximity to Lake Myvatn in Iceland. The Colonel's Regiment hiked to the top of it during mission 13. It is about 1km in diameter. The views from the top are incredible. Unfortunately, the crater floor is covered with humorous graffiti, of the form, "kiss my this", "suck my whatever", "my penis is so and so". Because of this, access to the crater floor is now forbidden.