The best way to enjoy the scenery is riding a bamboo raft along the Nine-Bend River.

Terrified shrieks echoed through the cave's eerie darkness, mingling with the screeches of the bats above us. People squirmed in panic but we were literally between two rocks and a hard place. Passing through A Thread of Sky in Fujian province's Wuyi Mountains means squeezing through a 163-m-long rift that is sometimes less than half a meter wide.

The tightest spots are pitch black at ground level but light shines several meters down through the crevice's opening high above, just enough to trace the silhouettes of bats flitting around. Someone said something about flying rats. My wife said something about vampires. Squashed between those gooey walls, excrement also came to mind.

Finally, we popped out of a slender crack into searing sunlight, which illuminated the limestone spires, looping rivers and fragrant tea gardens that make Wuyi Mountains a splendid travel destination.

Our subterranean experience seemed antithetical to the hours we had spent clamoring toward towering mountaintops. Wuyi's peaks average about 400 m, with its highest - the Three-Layer Peak - soaring 717 m skyward. They are part of a Cathayshan fold system, meaning that millions of years ago, the earth belched out tons of magma, which the sands of time ground into cones and pillars.