Water, fire and ice have combined to make some of the most spectacular scenery in the world -- from giant crystal caves to mud volcanoes and rock formations that look like works of art.
원문출처 : http://www.cnn.com/travel/article/natural-wonder-bucket-list/index.html
원문출처 : http://www.cnn.com/travel/article/natural-wonder-bucket-list/index.html