Blake Lively and Ryan Reynolds Photos - 'Captives' Premieres at Cannes - Zimbio
East of Reykjavik, Iceland lies the mountain, Hengill. Hengill was formed from a Palagomite tuff, it is a central volcano and has a giant magma chamber beneath it. When thick basalt lava flows cool, they form hexagonal cracks, called columnar joints. These can be found also in Ireland & Scotland.