One-Line Sky in Mount Wuyi

　　One-Line Sky in Mount Wuyi is located at the southwestern edge of the Mount Wuyi peaks and is the most spectacular cave in the area, renowned as a wonder of “uncanny craftsmanship.” The One-Line Sky is situated in a deep, quiet gorge on the southern side of the Second Bend of the Nine-Bend Stream. Within it stands an imposing giant rock hundreds of zhang long and thousands of ren high, named “Spirit Rock.” The top of the rock tilts outward, covering three adjacent caves: the Spirit Cave on the left, the Wind Cave in the middle, and the Fuxi Cave on the right. Entering the Fuxi Cave and proceeding deeper inside, if you look up, you will see a crack in the rock ceiling, as if split open by an axe, no more than a foot apart and about a hundred meters long, through which a sliver of daylight shines down like a blue rainbow spanning the sky—this is the breathtaking One-Line Sky.

　　There are many folk tales about the origin of the One-Line Sky. Some say it was sliced open by Peach Blossom Girl using an embroidery needle; others claim it was cleaved by the God Fuxi with his jade axe. However, scientific analysis suggests that the red rock layers of Mount Wuyi consist of interbedded sandstone, conglomerate, and shale, which are relatively brittle in nature. During the process of tectonic uplift, uneven stress caused slight fractures in the rock layers, forming what are known as “joints.” These vertical joints, or tiny fissures, gradually expanded and extended over years of dissolution and erosion by flowing water. Meanwhile, the soft shale at the base of the rock layers was eroded away, forming flat, shallow caves. As a result, the natural wonder of three caves aligned side by side with a single line of sunlight shining through came into being.

　　To view the One-Line Sky from within the Fuxi Cave, walk right along the stone fissure for several dozen steps to enter the Wind Cave. Visitors must move sideways, using both hands and feet to squeeze through. Rare mammals such as white bats can often be spotted inside the cave, adding an extra touch of wonder for visitors. The middle Wind Cave also connects to the One-Line Sky. A cool breeze blows gently through the stone fissure, and even in the height of summer, a brief stay here will make you feel a bone-chilling coolness, as if you were standing in front of a massive natural air conditioner. The two characters “Wind Cave” on the stone wall at the cave entrance are very eye-catching, inscribed by Xu Ziqiang of the Song Dynasty. After exiting the Wind Cave, walk around a stone corridor to reach the Spirit Rock Cave. Legend has it that a celestial being surnamed Ge once subdued demons here, hence the cave is also called the Gexian (Celestial Being Ge) Cave. Inside the cave is an ancient well called the Holy Water Well.

　　To the south of the One-Line Sky, facing it, lies Louge Rock. This towering, screen-like rock features several caves halfway up its face, believed to be the so-called immortal pavilions. To its left is another rock called Lan Rock, whose cliffs are covered in inscriptions. Beneath the rock lies a stone leaning against the cliff, with a path extending into it like a mountain pass, known as the Heavenly Gate. Among the scattered rocks in front of the cliff is also an amusing Snail Cave.

　　Travel Tips: 1. In the crevices of the One-Line Sky, you may spot white bats, a rare sight elsewhere.

　　2. Near the cave, you can find square bamboo, a rare variety among bamboos.