Steyr river, Austria

© guenterguni/Getty Image

Steyr River, Austria

This photo hasn’t been edited—the Steyr river in Austria’s Alps region is really this blue. The river flows through the Totes Gebirge (Dead Mountains), which refers to some areas with almost no vegetation—but not where this picture was taken! So how does a river descending from such a lifeless place have such vibrant water? The answer is found in the mountains themselves. When there’s rainfall or the surrounding snow melts, eroded sediment flows into the river. Heavier sediment sinks to the bottom and finer sediment stays suspended in the water. Light from the sun is scattered or reflected by the sediment, allowing us to see a beautiful, bright shade of blue. As such, this colourful stream is both beautiful to behold and tells us about its content.