Zhangye Danxia National Geopark, Gansu, China

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Zhangye Danxia National Geopark, China

Rocks are hardy heroes that have played a big part in human history since the Stone Age. They served as humanity's first tools and as nature's journals, carrying fossils of ancient organisms and documenting changes in geological processes. A great example of the latter is Zhangye National Geopark's Rainbow Mountains in China. This geological wonder displays vivid colours: reds, oranges, yellows and purples, which are layers of sedimentary sandstone rock. These unique mountains were formed through erosion over millions of years, creating the patterns and colours that define this landscape.