This is Reed Flute Cave in Guilin, Guangxi, China. Composed of natural limestone, this cave, which is filled with multiple of stalactites, stalagmites and rock formations, has been one of Guilin’s most visited attractions over the last 1200 years.
The cave itself, which is named after a type of reed used to make flutes, is over 180 million years old. Inside, there are more than 70 inscriptions written in ink, which can be dated back as far as 792 AD in the Tang Dynasty. Today, lighting has been installed to make the formations within look particularly stunning.