A beautiful sea of clouds appeared due to continuous rainfall within the Tianmen Mountain National Forest Park in Zhangjiajie City, central China's Hunan Province.

Tianmen Cave, or Heaven's Gate, is a natural, water-eroded cave. Clouds and mist constantly crossed through the gate, creating a spectacle for visitors. As the highest elevated cave of its kind in the world, it is one of the park's highlights.

(Cover image via VCG)

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