The word foss means waterfall in Icelandic. Gullfoss is located in the upper-middle reaches of the River Hvítá and originates from Langjökull (jökull means glacier). Many tourists visit to see the white water crashing dynamically over the waterfall. Lava showing columnar/planer joint and pillow breccia exposed along the side-wall of the waterfall reminds us of subglacial volcanic activity. Casting our eyes up, we can see the source of the river—Langjökull. The fast-flowing milky water of the glacial river, the pure water welling in the pahoehoe lava field, and the whitish blue colored hot spring in the geothermal area impressed me as symbols of Iceland's nature.