5. Rainbow Hills – Zhangye National Geopark, China
The most important feature of the region is the rainbow-colored rock formations; The rocks, available in red, orange, green, and yellow colors, are the result of sandstone and other minerals formed by tectonic movements that occurred 24 million years ago.
Zhangye Danxia is known for the unusual colors of rocks that are smooth, sharp, and several hundred meters high. They are the result of sandstone and other mineral deposits that formed over 24 million years. Wind, rain, and time have shaped extraordinary shapes in a variety of colors, patterns, and sizes, including towers, pillars, and ravines.
Declared a world heritage site by UNESCO in 2010, the region attracts many tourists. A series of boardwalks and access roads have been built to help visitors explore the rock formations.