Hverfjall Crater
Located near the eastern shore of Lake Myvatn in North Iceland stands Hverfjall, an impressive 4500 year old tephra explosion crater, measuring 396 meter (1,300 ft) high and 1 km in diameter. If you walk up the steep slope of this massive black ash cone, you are rewarded with an incredible view of the crater as well as the surrounding landscape. To provide a little perspective of the size, those tiny specs on the top right side are groups of people walking around the crater's rim. There are also people on the opposite side, but they are too small to see without enlarging the image.