On September 28, 2021, the Huanglong Scenic and Historic Interest Area in Songpan County of southwest China's Sichuan Province welcomed a sunny autumn day. As a UNESCO World Heritage site, it is known for its magnificent colorful water pools. These water pools are made of travertine, a form of limestone often deposited in hot springs. The water displays different colors based on the elements and algae in the water, as well as light absorption and reflection.

(All images via CFP.)

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