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, t(Cool Places In The World)
Setenil de las Bodegas (Cadiz) is one of the most curious towns in Spain for its urban setting. This one was constructed in the block of the river, where multitude of houses were constructed (without excavating) underneath the rocks.