Iceberg, Jökulsárlón, Iceland

A glassy iceberg comprised of ice believed to be more than 1,500 years old floats in Jökulsárlón, the glacier lagoon in southern Iceland. The oldest ice in the lagoon is almost like glass. Over time, the weight of ice and snow on top of it presses out any air. Without the obstruction of air pockets, blue wavelengths of light are able to penetrate deep into the iceberg, resulting in the blue color.